Re:Guidance on keeping seahorses

Pete Giwojna

Dear Barbara:

You’re very welcome and I’m glad I can be of service! It’s always a pleasure to help a hobbyist who is so keen on getting things right! Taking the time to do your homework, research the topic ahead of time, and ask a million questions before you take the plunge is always the best approach. That’s most commendable and I will be happy to answer all of your questions to the best of my ability, but in order to do them justice, I’m going to tackle them one or two at a time. That way I can provide you with more detailed responses that should be more useful and helpful for you, but it will take me a little longer to get around to all of your questions, so please bear with me in the meantime.

For starters, I’ll begin with your questions regarding what size of tank is best for seahorses and how long it needs to be established before you can begin stocking the old corral. Like all aquariums, moving a seahorse tank once it’s set up and established is a major operation that requires careful planning and a lot of hard work. Before it can be moved, you need to empty out almost all of the water, yet keep your substrate wet so that you don’t kill the beneficial bacteria in your biofilter volume while transporting the tank, and you must temporarily house the fish and invertebrates in buckets or other containers while the move is being made. An aquarium is not meant to be portable — they’re much too heavy and the danger of cracking the tank or creating leaks too great to attempt to move a tank with all the decorations and water in place, so take care when you select the location for your aquarium, as discussed below.

Setting Up the Aquarium for Greater Seahorses

Size and Location.

The size and the location of the tank are the first things you must consider when preparing an aquarium for seahorses. Unless you will be keeping one of the miniature breeds of farm-raised seahorses, such as Hippocampus zosterae, H. breviceps, or H. tuberculatus, it’s best to start with the largest aquarium you can reasonably afford and maintain (the taller, the better). In general, a tank of at least 40 gallons (150 L) is preferable since that’s the size when one begins to see significant benefits in terms of the greater stability a larger volume of water can provide. An aquarium of 40-gallons or more will be more resistant to overcrowding and to rapid fluctuations in temperature, pH, and salinity than smaller setups. The larger the aquarium the larger the margin for error it offers the aquarist and the greater the benefits it provides in terms of stability.

It is equally desirable to select an aquarium at least 20-inches high when keeping the greater seahorses. They need the vertical swimming space to perform their complex mating ritual and successfully complete the egg transfer, which is accomplished while the pair is rising through the water column or drifting slowly downwards from the apex of their rise. If the aquarium is too shallow, eggs will be spilled during the transfer from the female to the male’s brood pouch, and mating becomes increasingly difficult or impossible below a certain minimum depth. A tall aquarium can also help protect the seahorses from depth-related health problems such as bloated pouch and certain forms of Gas Bubble Disease.

When setting up the aquarium, our goal is to create a stress-free environment for the seahorses, and some potential stressors can be eliminated in the planning stage simply by choosing the right location for the tank. For example, it should be located in a low-traffic area away from heat sources and cold spots. Avoid placing it adjacent to a radiator, fireplace, a door that opens to the outdoors, or heating and cooling vents. It’s great to have your aquarium in an air-conditioned room, but avoid positioning it too close to the cooling unit. Avoid placing the aquarium in front of a window for the obvious reasons but also because direct sunlight can make it very difficult to control nuisance algae. Siting the tank where it receives a little indirect sunlight, however, is not a bad idea at all since that will help establish a natural day/night cycle that changes with the seasons, and such environmental cues can play an important role in regulating breeding.

Choose a location that minimizes shock and vibration as well as excess noise and foot traffic. The medium of water transmits certain sounds wonderfully well — far better than air, in fact — and like all fishes, seahorses have organs specially designed to detect such vibrations, and are sensitive to external noises and outside sources of shock and vibration (Giwojna, Jun. 2002). Whether it’s a clunky air pump or compressor, the buzzing ballast from an aquarium reflector, the rattling impeller from a noisy power filter, or something totally unrelated to the aquarium, like a nearby clothes washer/dryer, dishwasher, stereo, television or some such appliance, any source of bad vibes can subject seahorses to chronic low-level stress (Giwojna, Jun. 2002).

To avoid this sort of stress, choose the location for your seahorse tank with care, dampen all potential sources of shock and vibration, and provide a pad (a sheet of Styrofoam insulation or cork is ideal) beneath the tank to deaden vibrations and soften any shocks that might otherwise be absorbed through the base of the aquarium (Giwojna, Jun. 2002). The aquarium should be situated in a relatively quiet room away from major traffic areas, blasting stereos, blaring TVs and noisy kids that can’t resist tapping on the glass to see how the fish react. If you have modified your laundry room, utility room, or workshop so it can do double duty as your fish room, you may want to find a less mechanically cluttered area for your seahorses (Giwojna, Jun. 2002).

Stray voltage is another common cause of chronic stress for seahorses and other aquarium inhabitants, as well as a much more prevalent problem than most hobbyists suspect (Giwojna, Jun. 2002). Installing a grounding probe in the tank easily prevents it, and every seahorse setup should be equipped with one. A titanium grounding probe is an inexpensive investment that can safeguard the health of your seahorses (Giwojna, Jun. 2002). Think of it as an extraordinarily cheap, yet effective life insurance policy that can save your fish — and your hide — in the event of an electrical accident while working on your tank. Even better, install a Ground Fault Interrupter on the electrical outlet(s) where you plug in your aquarium equipment.

When choosing the location for your tank, bear in mind that a large aquarium in excess of 40-gallons and at least 20 inches tall is a massive object (Indiviglio, 2002). When completely furnished with water, rockwork, and gravel, such an aquarium can easily weigh 500-1000 pounds, depending on its exact dimensions. Make sure the floorboards in the fish room and the aquarium stand you select are up to the task and can support a half-ton or more of dead weight.

Establishing the Aquarium.

Rather than discussing all of the different filtration options and systems that are commonly used to keep the greater seahorses, I am going to focus on one particular method that I have found produces the best results for me and describe how to set up such a system in detail. One reason I prefer this method is that it is very versatile and can easily be adapted to suit almost anyone’s needs and interests.

The setup for greater seahorses I prefer, and which most hobbyists favor at this time, is know as a “Sea-Horses-Only-With-Live-Rock” system, or a SHOWLR tank for short. It is simplicity itself, extremely effective for seahorses, and endlessly adaptable. It is suitable for tanks from 5 gallons to 500 gallons, and can be adapted successfully to suit the simplest setups or the most complex, high-tech systems. The primary components of the SHOWLR tank include:
(1) a thin layer of live sand (3/4" to 1" deep) for the substrate;
(2) 1-2 pounds of well-cured live rock per gallon of water;
(3) a quality protein skimmer;
(4) and an external power filter to provide water movement and supplemental filtration; power heads can be added as needed to increase circulation and eliminate dead spots.

Live Rock.

The one indispensable part of a SHOWLR system is the foundation of live rock. The live rock is the living, breathing, heart and soul of the system, which provides the bulk of the biological filtration as well as some denitrification ability and shelter and habitat for countless critters and microfauna. The porous interior of the rock supports large populations of the beneficial oxygen-loving Nitrosomonas and Nitrobacter bacteria that breakdown deadly ammonia and nitrite into less toxic substances (primarily nitrate). Deeper inside the live rock, where oxygen levels are nil, anaerobic denitrifying bacteria take hold and complete the nitrogen cycle, breaking down nitrate into harmless nitrogen. This helps keep the nitrate levels in the seahorse tank low. As a result, live rock is superior to most other forms of biofiltration, which lack this final anaerobic step and cannot carry out denitrification. This makes live rock doubly good at maintaining optimum water quality.
Equally important, the rockwork provides cover for the seahorses. By this, I mean the rock allows the seahorses to hide and conceal themselves completely whenever they feel the need. Seahorses are shy, secretive creatures that rely on camouflage as their primary means of protection, and if they feel too exposed and vulnerable, it can be stressful for them.

Despite its beauty, natural appearance and the many benefits it provides, some hobbyists avoid live rock like the plague for fear that they may introduce harmful pests to their aquarium along with the live rock. This is a valid concern since potentially harmful hitchhikers like mantis shrimp, fireworms, aggressive crabs, hydroids and Aiptasia rock anemones are very often unseen and unwanted tenants of live rock. They insinuate themselves throughout the live rock in nooks and crannies, and multitudes of these squatters may have taken up housekeeping in a good-sized piece of rock unbeknownst to the unsuspecting aquarist. They conceal themselves within the labyrinth of rock and often escape even the closest scrutiny undetected.

But with a little care this is one time when aquarists can have their cake and eat it too. There are a number of ways to take advantage of all the benefits live rock provides without risking unleashing an epidemic of tenacious rock anemones or turning Jack-the-Ripper loose in your tank reincarnated in the form of a thumb-splitting Stomatopod.

For instance, some seahorse keepers treat live rock with fenbendazole for a period of 3-4 days to eradicate such pest before placing it in the aquarium. Fenbendazole is an anthelmintic agent used for deworming large animals such as horses (Abbott, 2003), and 1/8 teaspoon of granular fenbendazole per every 10 gallons of water will indeed kill worms, including bristleworms, as well as hydroids, anemones and certain other Cnidarians (Liisa Coit, pers. com.). It will not harm your biofilter, most macroalgae, copepods or most types of shrimps and other crustaceans, or most kinds of snails (Liisa Coit, pers. com.), so it leaves most of the desirable life on the rock intact. Be sure to check the water for ammonia and nitrite if you use fenbendazole for pest control this way, since the sudden die off of worms and Aiptasia anemones is likely to cause ammonia and/or nitrite spikes that must be controlled with water changes.

By and large, bristleworms are beneficial scavengers and sand sifters unless their numbers get out of hand, so a better option for many seahorse keepers is to keep the Aiptasia and bristleworm population in check using some means of biological control. Peppermint Shrimp (Lysmata wurdemanni) love to dine on Aiptasia rock anemones and several of these attractive shrimp will do a fine job of eradicating them from the aquarium. Certain nudibranchs (Berghia sp.) also feed on Aiptasia. Likewise, small Arrow Crabs (Stenorhynchus sp.) will keep the bristleworm population at a manageable number. Any mantis shrimp or aggressive crabs that happen to slip by are generally fairly easy to trap and remove, and commercially made traps are available for that very purpose.

Treating the live rock with a hypersaline dip is another excellent technique for ridding it of unwanted pests. This method doesn’t kill the critters outright but merely drives them out of the rockwork so you can selectively cull through them. Another advantage of this method is that leaves all the desirable life on the rocks intact and unharmed.

To use this technique, simply place your newly arrived live rock in an inert container filled with saltwater at a specific gravity of 1.035 to 1.040 for one minute before you cure it. Invertebrates cannot tolerate rapid changes in salinity, so all the mobile inverts in the rock will immediately abandon there hidey-holes and bale out of the rock like rats deserting a sinking ship. After a full minute in this extra-salty bath, the evacuation will be complete, and you can remove the now pest-free live rock and sort your catch. Cull the invertebrates left behind in dipping container, discarding the pests you don’t want while retrieving any of the refugees you might like to add to your system. One full minute in the hypersalinity is enough to drive out all the active invertebrates such as mantis shrimp (Stomatopods), crabs, and assorted worms of every description, yet this brief period of immersion will not harm encrusting organisms or sessile life.

Cautious aquarists who want to make doubly sure that their live rock is free of unwanted hitchhikers can follow the hypersaline bath with a regimen of fenbendazole. The hypersalinity will drive out the mobile pests while the fenbendazole will eradicate any remaining sessile invertebrates that could be harmful, such as anemones, hydroids and other Cnidarians. The one-two punch of hyposalinity plus fenbendazole produces pest-free rock.

Get the biggest aquarium you’re comfortable with and fill it with up to 1-2 pounds of well-cured, debugged live rock per gallon, supplemented by a quality protein skimmer and an external power filter, to serve as the basic filtration system for your seahorse setup. For the protein skimmer.

An external power filter is a valuable addition to a SHOWLR setup for several reasons. It will provide added water movement and circulation for your aquarium, as well as accommodating any mechanical or chemical filtration you may desire. A bewildering array of filtration options are available today, including a myriad of canisters and hang-on-the-back models, most of which will do the job reasonably well. Even the trusty old standbys, undergravel filters and air-operated sponge/foam filters, are still acceptable choices for a standard seahorse setup.

But wet/dry trickle filters are probably the most desirable units for the seahorse keeper if the aquarium has adequate space (behind or beneath it) to accommodate such a unit and the hobbyist can afford one. They are top-of-the-line units that feature a thin film of water trickling over filter media with an ultra-large surface area, thereby allowing maximum air-water contact. This provides excellent oxygenation with efficient offgassing, which is very important for seahorses. It helps keep dissolved oxygen levels high, CO2 low, and effectively prevents gas supersaturation, which can sometimes contribute to serious problems for our aquatic equines. As a added benefit, wet/dry trickle filters can also provide remarkable biological filtration, which is not really needed for a SHOWLR system, but which can give you a real nice edge by further increasing your carrying capacity and boosting your margin for error accordingly. And they can provide all the biological filtration you need for those hobbyists who opt not to use live rock in their seahorse tanks.

The type or brand of supplemental filter you choose for your SHOWLR tank is not critical, but there are certain desirable features you want to look for in any filter that will be used for seahorses. For example, it should provide good surface agitation and water movement with adjustable flow. The intake tubes should reach all the way to the substrate (add extenders if they do not) and be screened off or otherwise shielded so they cannot “eat” a curious seahorse. The filter must provide efficient oxygenation and gas exchange and be able to accommodate mechanical and biological filtration media such as activated carbon and polyfilter pads. A prefilter is very desirable, as is a “waterfall” return.

A thin layer of live sand, preferably black, is the ideal substrate for a SHOWLR tank. It is bioactive, aesthetically pleasing, and is a fine-grained sand well suited for the various snails that form an essential part of the cleanup crew for a seahorse tank. I find the dark color shows off my seahorses and macroalgae to great effect and enhances the appearance of tank in general. (As long as it’s fine enough I’ve never had any problems with seahorses "snicking" up sand in the aquarium. They will do so on occasion when feeding off the bottom, but never have any difficulty at all expelling it again as long as it’s fine grained.)

The depth of a shallow sand bed like this is a crucial factor. Too deep, and you risk anaerobic dead spots where deadly hydrogen sulfide gas can form. Too shallow, and there will be less surface area to support beneficial nitrifying bacteria and Nassarius snails and other beneficial burrowers may feel vulnerable and exposed. A bed of live sand 3/4-inch to 1-inch deep is just right for the main tank. A properly layered Deep Live Sand Bed (DLSB) with a full complement of sand shifters also works well with seahorses, but is best confined to a sump rather than the display tank due to the seahorse’s heavy waste production.

As for the aquarium water, I have found Instant Ocean artificial sea salt works very well for seahorses. A good submersible aquarium heater such as a Visi-Therm is usually necessary to keep the aquarium temp from falling below 72-degrees F.

Hitching posts can be either live or artificial marine sea grasses, algae and corals. If you decide to try an assortment of colorful artificial corals, seahorses often prefer red or orange pieces. Many hobbyists report good results using artificial finger sponges, staghorn coral, octopus coral and pillar coral in the appropriate colors to keep their seahorses looking their brightest (SigNature Coral Corporation). They look entirely natural and lifelike, with lots of branching projections that make great hitching posts for seahorses. Oh, and their cup coral makes a great ready-made feeding station! They can be obtained from the following website:
Click here: SigNature artificial Coral Corporation

For live hitching posts, I prefer decorative marine plants or macroalgae in a variety of shapes and colors and color–reds, golds, and yellows in addition to green varieties, some tall and feather, some short and bushy–to provide them with natural hitching posts and shelter. I like to start with Hawaiian Ogo (Gracilaria sp.) and Bonzai Ogo (Gracilaria sp.) along with any of the plumed (feathery) or long-bladed Caulerpa, such as Caulerpa sertularioides, Caulerpa mexicana, Caulerpa ashmedii, Caulerpa serrulata or Caulerpa prolifera. They will do fine under normal aquarium lighting.

The aquarist should also be diligent at harvesting any fast-growing Caulerpa in the tank on a regular basis. Periodically removing a portion of the Caulerpa is a very effective way to export nitrates, phosphates, and other nutrients from the aquarium.

When pruning back or harvesting the Caulerpa, take care not to cut or sever the plants. Cutting it or breaking off too many fronds causes the Caulerpa to leach undesirable substances from the cut or broken ends into the water. Not only is this bad for the water quality, it can sap the colony and perhaps trigger one of the dreaded "vegetative events," during which the main colony dies off. The best way to harvest the Caulerpa is to carefully extract unbroken continuous fronds. The idea is to thin out convenient strands of Caulerpa from the colony, gently pulling up entire fronds, intact and unbroken. This is a wonderful way to remove nitrogenous wastes (which the plants utilize for growth like fertilizer) from the aquarium, and if done consistently, it will prevent the colony from going sexual.

If you don’t have them already, you will also need some saltwater test kits to cycle your tank, monitor conditions in your aquarium, and keep track of the water quality. The basic test kits you’ll need to keep track of the aquarium parameters are ammonia, nitrite, and nitrate, plus a hydrometer to check specific gravity and an aquarium thermometer (if you don’t have one already). You’ll need to get separate test kits for ammonia, nitrite, and nitrate, and I recommend fasTest or Salifert kits for saltwater. I also like the SeaTest hydrometers–convenient, easy to read, and reliable.

A test kit to measure the levels of dissolved oxygen is also useful for seahorse keepers. The Tetra Oxygen Test Kit (TetraTest 02) is a good liquid reagent test kit for fresh or saltwater with simple color scales for comparing readings that tests for 02 in the range of 2-14 ppm (the optimum dissolved O2 level is 6-7 ppm). It will cost you between $8.50 to $14 depending on where you shop and should be available at any well-stocked LFS. Salifert also makes a nice 02 Test Kit (their 02 Profi-Test) that will run you about $20.

Back to the Basics: A Simple Setup for Seahorses.

If you’ve never kept an aquarium with live rock (LR) or live sand (LS) before, you may be uncomfortable with the idea of setting up and maintaining a SHOWLR tank, which relies on LR and LS as the primary means of biofiltration. Or your hobby budget may not permit expensive items such as a protein skimmer or wet/dry trickle filter, let alone a multi-chambered sump/refugium or loads of live rock.

If so, don’t despair! Seahorses can certainly be kept very successfully in far simpler setups, as long as you are aware of the limitations of such systems. For example, the filtration system can be as basic as a set of well-maintained reverse-flow undergravels that covers the bottom of the tank completely. I know undergravel filters are considered old-fashioned technology nowadays, but they are inexpensive, utterly reliable and foolproof (no moving parts), easy to install, require no modification whatsoever, and work extremely well for seahorses. An inexpensive diaphragm air pump will operate the filter and provide all the aeration you need, or you can upgrade to powerheads for greater efficiency and extra water movement.

For the substrate with your rfeverse-flow undergravel filters, use a coarse bed of good calcareous aquarium gravel such as dolomite, aragonite, or crushed oyster shell 2-3 inches deep, since the buffering ability of such substrates will help maintain good pH.

It is a good idea to supplement the undergravels with an inexpensive hang-on-back filter or canister to provide better circulation and accommodate chemical filtration media.

This is a very simple, inexpensive aquarium that’s extremely easy and economical to set up and operate, yet it can be very successful if used within its limitations. For instance, undergravel filters are notorious nitrate factories and the hobbyist must take measures to compensate for this fact. This simple system relies totally on water changes to control nitrates. There is no live rock or live sand bed to provide denitrification, no algal filter or denitrator in a sump, and no protein skimmer to remove organics before they enter the nitrogen cycle. This limits the carrying capacity of the tank and makes an accelerated maintenance schedule and more frequent water changes an absolute necessity.

I recommend weekly water changes of a least 25% for such a system. Use a gravel washer to clean a different portion of the gravel bed (no more than 25%) each week and keep the tank under stocked. If you are diligent about aquarium maintenance, perform water changes religiously, and limit yourself to fewer seahorses that you feed carefully, you will find that a simple system featuring undergravel filters can be very successful. But if you are negligent with regard to maintenance, skimp on water changes, or tend to overcrowd or overfeed your tanks, this system will be very unforgiving.

Whichever systems is best for you — a basic SHOWLR tank, a modified reef tank complete with a dual-purpose sump/refugium, or the simplicity of a set of reverse-flow undergravels — it’s best to get your aquarium accessories and filtration equipment from the same fish dealer who sold you the aquarium. He’ll make sure that the equipment will fit properly and install easily in that type of tank.

Once you’ve rounded up the aquarium, equipment, and accessories you need, your next task is to prepare the tank for cycling. Until it has cycled, your aquarium will be unable to support life. Cycling simply means to build up a healthy population of beneficial bacteria in your tank that can carry out the nitrogen cycle and breakdown your fishes’ waste products.

Ammonia (NH3), nitrite (NO2), and nitrate (NO3) are all nitrogenous (nitrogen containing) wastes. All living aquarium animals whether they be fish or invertebrates excrete these wastes, and they are also produced by the decay of protein-containing organic matter (uneaten food, detritus, dead fish or inverts, etc.). The nitrogen cycle breaks down these wastes in a series of steps into nitrogen gas (N2) which leaves the aquarium as bubbles.

The nitrogen cycle begins with ammonia, which is highly poisonous. In the first step of the cycle, Nitrosomonas bacteria reduce ammonia to nitrite, which is also very toxic. In the second step of the nitrogen cycle, Nitrobacter bacteria convert the nitrite to nitrate, which is relatively harmless but becomes harmful when it accumulates in high enough levels. In the third and final step of the cycle, denitrifying bacteria then convert the nitrate into completely harmless N2, which of course bubbles out of the tank as nitrogen gas. In this way, thanks to the nitrogen cycle, dangerous wastes are converted into progressively less harmful compounds and finally removed from the aquarium altogether.

When we set up a new aquarium, and wait for it to cycle, we are simply allowing a big enough population of these different types of bacteria to build up in the biofilter to break down all of the wastes that will be produced when the aquarium is stocked. If we don’t wait long enough for the cycle to complete itself and the biofiltration to become fully established, and hastily add too many specimens to a new aquarium too soon, they will die from ammonia poisoning or nitrite toxicity. This is such a common mistake among us impatient aquarists, that when fish get sick and/or die from ammonia/ntrite poisoning, it is commonly called the "new tank syndrome."

When your aquarium has completely cycled, the ammonia levels will stay at zero because, now that your biofilter is fully established, there is a large enough population of aerobic (oxygen loving) nitrifying Nitrosomonas bacteria to reduce all of the ammonia to nitrite as fast as the ammonia is being produced. The nitrite levels will likewise stay at zero because there is also a large enough population of aerobic (oxygen loving) nitrifying Nitrobacter bacteria to convert all of the nitrite to nitrate as fast as the nitrite is being produced.

The nitrate levels ordinarily continue to build up, however, because there are simply not enough anaerobic (oxygen hating) denitrifying bacteria to convert all of the nitrate that’s being produced into nitrogen gas (N2). Since nitrates are being produced faster than they can be transformed to nitrogen gas, the excess nitrates accumulate steadily in your aquarium. That’s perfectly normal, since the denitrifying bacteria that carry out that final step, the conversion of nitrate (NO3) to nitrogen (N2), are anaerobes that can only exist in the absence of oxygen. For our aquariums to support life, and for the fish and invertebrates to breathe and survive, our tanks must be well aerated and well circulated so that there’s plenty of dissolved oxygen in the water at all times. That means there are normally very few areas in our aquariums where anaerobic denitrifying bacteria can survive, limiting their population accordingly (which is generally good, since some anaerobes produce deadly hydrogen sulfide gas during the decay of organic matter and would poison our tanks if allowed to proliferate).

Consequently, most aquariums lack a sufficient population of anaerobic denitrifying bacteria to complete the nitrogen cycle and convert nitrate to nitrogen as fast as the nitrates are being produced. The only way to keep the nitrates from building up to harmful levels in such setups is with regular water changes and by harvesting Caulerpa or other macroalgae periodically after it has utilized nitrates for growth. Overcrowding, overfeeding, or under filtration exacerbate the problem by resulting in more nitrates being produced and more frequent water changes being required to control the nitrate levels.

Live rock helps because the oxygen-poor interior of the rock allows anaerobic denitrifying bacteria to grow and break down nitrates. A deep live sand bed (DLSB) also helps because anaerobic denitrifying bacteria can flourish and break down nitrates at a certain depth below the sand where oxygenated water no longer penetrates, but a DLSB can sometimes be difficult to set up and manage properly if you’re inexperienced with live sand. Both live rock and deep live sand beds give aquaria denitrification ability — the ability to complete the cycle and convert nitrate to harmless nitrogen. Ordinarily, about 1-2 pounds of live rock per gallon is recommended – that amount of LR will provide your aquarium with all of the biofiltration you need, as well as significant denitrification ability. You will keep nitrates at harmless levels by performing regular water changes, harvesting Caulerpa macroalgae periodically, and good aquarium management.

Prepare your aquarium for cycling by setting your system up with just freshwater at first, attaching the equipment and apparatus (filter, aeration, circulation, heater, skimmer, lighting, accessories) and testing it all for a day or so to make sure you have everything in place, and that it works. Once assured that everything’s operating properly and there are no leaks, go ahead and add the substrate, salt mix, and aquarium décor, and leave everything running for a good week, allowing the various components and water to "settle in" before adding your microbes and "seeding" the tank with beneficial bacteria that will eventually establish your biofilter.

If you are using live rock, it contains all the bacteria needed to seed the tank, so all you have to do is position the live rock in attractive arrangements and wait for the population of nitrifying and denitrifying bacteria to build up and stabilize.

If you are not using live rock, there are a number of different ways to seed the tank with bacteria and feed it with ammonia so cycling can proceed. Two popular methods are the fishless cycle, which I recommend, and the use of hardy, inexpensive (i.e., expendable) fish to produce ammonia and cycle the aquarium. Often used for this method are marine damselfish or mollies, which can easily be converted to saltwater. Both are very hardy and generally survive the cycling process, but I find this method to be needlessly hard on the fish and exposing them to the toxic ammonia and nitrite produced during cycling certainly causes them stress. Damselfish are far too aggressive and territorial to leave in the aquarium afterwards as tankmates for seahorses. Mollies are a possibility, but they really look out of place in a saltwater setup.

So all things considered, I suggest you try cycling your tank without fish. It’s really very easy. To use the fishless cycle, you need to add something else that will increase the ammonia level so the nitrifying bacteria can build up. I like to use a piece of cocktail shrimp (regular uncooked eating shrimp from the grocery store) and leave this in the tank to decay during the whole cycle. The decaying shrimp produces plenty of ammonia to kick-start the cycling process.

After about 3 days after you add the shrimp, you will notice a spike in ammonia levels until the Nitrosomonas bacteria build up enough to break down the ammonia. When that happens, you will notice the ammonia levels rapidly dropping. (If for some reason your ammonia does not hit the top of the charts initially, you may want to add another piece of shrimp.)

The byproduct of ammonia is nitrite, and during this stage of the cycling process, as the ammonia falls, you will have a corresponding increase in nitrites until the population of Nitrobacter bacteria builds up. Nitrite levels will then fall as the Nitrobacter convert the nitrite to nitrate.

It is important to use your test kits every day or two when cycling your tank to monitor the progress of the process. As described above, at first you will see a rapid rise in ammonia levels with no detectable nitrite or nitrate. Then, as Nitrosomonas bacteria begin converting ammonia to nitrite, the ammonia levels will fall and nitrite readings will steadily rise. Nitrite levels will peak as the ammonia drops to zero. Next, Nitrobacter will begin converting the nitrite to nitrate, and your nitrite readings will fall as the level of nitrate rises. Finally, after the nitrites also read zero, you are ready to stock your tank. At this point, your ammonia and nitrite levels should both be zero, nitrates will be building up, and algae will usually begin to grow. This will tell you that your biofilter is active and functioning properly, and that you can now safely begin stocking the tank. It generally takes about 3-6 weeks to cycle a tank this way from scratch.

If you any more questions about cycling, the following link should provide you with answers:
Click here:

So you don’t have to wait several months for your new aquarium to stabilize and mature before you add any seahorses, Barbara, but you will need to wait several weeks for the aquarium to cycle and the biofiltration to become fully established before you begin stocking the tank.

Once the tank has cycled, It’s a good idea to begin stocking your system by adding the cleanup crew first. For seahorses, I recommend a cleanup crew consisting of a combination of snails and micro hermits at a density of perhaps 1-2 janitors per gallons. You can include some Astrea and Cerith snails, but make sure you have plenty of Nassarius snails. Nassarius snail are terrific detritivores and amazingly active for snails. Try to avoid Turbo snails, however, at all costs. Turbos are big and very delicate, causing pollution problems when they inevitably die. For hermits, stick with a mixture of Dwarf Blue-leg (Clibanarius tricolor), Left-handed (Calcinus laevimanus), and Scarlet Reef hermit crabs (Paguristes cadenati). That’ll give you a good balance of herbivores, omnivores, and detritivores that are all active scavengers and completely compatible with seahorses.

Daily Maintenance:

Your daily chores begin with feeding your livestock and cleaning up afterwards. Considering that captive-bred seahorses are trained to eat enriched frozen Mysis as their staple diet, proper feeding means assuring that each of your steeds gets it’s fill without overfeeding them, and that you clean up any leftovers promptly. Use of a feeding station, target feeding slow eaters, and a good cleanup crew are all helpful in that regard.

Dip tubes, basters, and long-handled nets are useful for gleaning leftover Mysis, and while you’re at it, you should also take a moment to police the bottom for any debris, accumulated plant matter, and fecal pellets. Promptly removing such waste materials, before they breakdown and enter the nitrogen cycle, will go a long way toward towards assuring good water quality, controlling nitrates, and keeping your substrate clean.

When feeding your seahorses, take advantage of this opportunity to conduct a close-up, daily inspection of every specimen in his tank. These detailed examinations are perhaps the most important of the seahorse keeper’s daily chores, yet many aquarist ignore this vital task altogether. Such inspections make it difficult not to notice any subtle changes in my seahorse’s appearance or behavior that might signal impending problems with disease or the water chemistry. That’s extremely important, since seahorses hide their illnesses so well, and the sooner such potential problems are detected, the easier they are to cure or prevent. Due to there sedentary lifestyle, it can be difficult to detect when a seahorse has a problem. The first signs of trouble are often very subtle: an increase in respiration, a decrease in eye movement or appetite, a localized change in pigmentation or the appearance of a tiny nodule the size of a goosebump or mosquito bite.

So take a moment to enjoy the show when feeding your seahorses. Make sure they all show up for mess call, are acting normally, and have a well-rounded abdomen when they’re done eating. Watch them swim and move around as they answer the dinner bell. Make sure they’re not having difficulty maintaining their equilibrium or experiencing any buoyancy problems. Observing their behavior at mealtimes makes it hard to miss when one these chowhounds is off its feed, which is often an excellent early indicator that something’s amiss in the aquarium.

Likewise, keep a close eye on the health of any sessile animals and benthic invertebrates in the tank, such as sponges, sea cucumbers, tunicates, corals, snails and starfish. It can be difficult to determine if inactive animals like these are alive and well or on their way out, and nothing fouls a tank faster than the undetected death of a large turban snail or sea star or sponge. This is especially important if you’re keeping your seahorses in a modified reef tank. One neglected mushroom coral turning to mush can cause an ammonia spike that imperils all the other invertebrates and thus threatens the entire tank.

Make a quick check of the electrical equipment as well. See that the aquarium temperature is holding where you want it to assure that the heaters are working properly. Double check the filters, pumps, powerheads and lights to make sure they are all operating and producing normal flow rates. Decreased flow could indicate a malfunction or indicate that the filter is dirty and clogged and needs to be cleaned. Make sure the protein skimmer is doing its job: adjust the bubble column if needed and empty the collection cup if necessary.

Checklist of Daily Chores:

*Daily inspection of livestock.
*Temperature check.
*Equipment check.
*Empty the collection cup on your skimmer.
*Clean up leftovers and debris.

Weekly Maintenance.

It’s important to check the water level of the aquarium at least once a week. It will drop steadily due to evaporation, increasing the salinity of the aquarium water in the process. If the water level falls too far, it can break the siphon on return tubes and intakes, filters can become airlocked, and protein skimming may be disrupted. Remember, only the water evaporates; all of the salts and minerals it contains are left behind. When replacing the water lost to evaporation, top off the tank with freshwater, not saltwater. The water used to top off the tank should be treated to remove chlorine and chloramines, aerated, and adjusted to roughly the same temp as the aquarium water.

Salt creep and condensation of aquarium water on the underside of the aquarium cover can led to the build up of salt deposits on the glass, light fixture, hood or lid of the tank, or on various pieces of equipment. Not only is this unsightly, it can drastically reduce the light level in the aquarium and cause electrical shorts. It’s a good idea to remove these crusty accumulations periodically by cleaning them off once a week or so with a damp cloth or sponge reserved for aquarium use only.

The aquarium glass itself should likewise be cleaned at least once a week. Algae scrapers or algae sponges (often mounted on strong magnets) can be used to clean the interior of the tank. Different tools are available for cleaning glass tanks and easily scratched acrylic tanks, so be sure you use the right kind for your setup.

The exterior aquarium glass can be cleaned using plenty of elbow grease and crumpled up newspapers. Surprisingly, old newspaper has just the right texture, consistency and absorbency to do a marvelous job of polishing aquarium glass, and something about the newsprint prevents streaking of the glass on the viewing surfaces. Slightly damp newspaper is perfect for keeping the aquarium glass looking immaculate.

It’s also advisable to break out your test kits on the weekends and check the key measurements of your water chemistry. Test the pH for sure since it inevitably declines over time. A significant drop in pH may require the addition of a buffer to correct it or indicate the need for a water change. Get out your hydrometer and test the specific gravity. It may have fallen due to salt creep or the formation of salt stalactites, or it may have risen due to evaporation. Adjust it accordingly. Nitrate levels will rise steadily over time so they must be monitored as well. We want to keep nitrates below 20 ppm (lower if your setup is a modified reef system). Many systems rely primarily on water changes to control nitrates, and a persistent rise in nitrate levels calls for a water exchange.

Checking your dissolved oxygen level can be especially revealing. A decrease in O2 is often a harbinger of trouble, and it thus alert the aquarist to a dangerous situation while there’s still time to correct it. For instance, an unexpected drop in O2 can be an indication of overcrowding or overfeeding, or it can be a sign that the tank and/or the filters are overdue for a good cleaning, or reveal the need for better circulation and surface agitation. Take appropriate measures to correct the problem, until the oxygen readings are back to normal (6 – 7 ppm is optimal).

If you don’t already have test kits of your own for measuring ammonia, nitrite, nitrate, pH and dissolved oxygen, as well as a hydrometer for measuring specific gravity, you should invest in some and learn how to use them, Monique. The basic test kits are inexpensive and easy to read, and you need to have them on hand for use at the first sign of a problem. When there is trouble, finding out if the tank has experienced an ammonia splike, or the pH has crashed, or the dissolved oxygen levels are dangerously low can’t wait for the aquarium service guy to check it.

The aquarist should also be diligent at harvesting any fast-growing Caulerpa in the tank on a regular basis. Periodically removing a portion of the Caulerpa is a very effective way to export nitrates, phosphates, and other nutrients from the aquarium. When pruning back or harvesting the Caulerpa, take care not to cut or sever the plants. Cutting it or breaking off too many fronds causes the Caulerpa to leach undesirable substances from the cut or broken ends into the water. Not only is this bad for the water quality, it can sap the colony and perhaps trigger one of the dreaded “vegetative events,” during which the main colony dies off. The best way to harvest the Caulerpa is to carefully extract unbroken continuous fronds. The idea is to thin out convenient strands of Caulerpa from the colony, gently pulling up entire fronds, intact and unbroken. This is a wonderful way to remove nitrogenous wastes (which the plants utilize for growth like fertilizer) from the aquarium, and if done consistently, it will prevent the colony from going sexual.

Checklist of Weekly Chores:

*Top off tank with freshwater to replace water lost to evaporation.
*Remove salt buildup.
*Clean aquarium glass (inside and out).
*Check basic water quality parameters:
(pH, specific gravity, nitrate, etc., and especially dissolved O2)
*Harvest Caulerpa.
*Partial water change (if indicated).

Monthly Maintenance.

Depending on the number of fish kept and the filtration system you use, external filters should be cleaned about every month. For safety’s sake, take care to unplug all the electrical equipment before cleaning it and performing this type of maintenance. Rinse or replace the prefilter and filter pad(s) or sponges that provide mechanical filtration. Chemical filtration media, such as activated carbon, ion exchange resins, poly-pads, or various other purification media, should also be recharged or replaced at this time. Run a bristle brush through siphon tubes to clean them.

Aquarium decorations (coral skeletons, plastic plants, artificial corals) that have become overgrown with unsightly algae may also be cleaned monthly. They can be cleaned with bleach or soaked in one of the new oxygen-based cleaning products, rinsed very thoroughly, and then air dried in the sun.

More importantly, now is the time to perform the monthly water change. I like to combine a 25%-35% water change with a thorough aquarium clean up. Siphon around the base of the rockwork and decorations, perhaps vacuum the top ½-inch of the sand or gravel, and administer a general system cleaning. The idea is to remove any accumulated excess organic material in the uppermost layer of the sand/gravel bed, top of the filter, or tank that could degrade your water quality, serve as a breeding ground for bacteria or a reservoir for disease, or otherwise be stressing your seahorses. [Note: when cleaning the filter, your goal is to remove excess organic wastes WITHOUT disturbing the balance of the nitrifying bacteria. Do not dismantle the entire filter, overhaul your entire filter system in one fell swoop, or clean your primary filtration system too zealously or you may impair your biological filtration.]

There are a few accessories you should keep on hand to make water changing easier: one or more large capacity plastic garbage cans or rubbermaid vats for mixing up new saltwater; a small powerhead for stirring and circulating the water while it mixes; a submersible heater to adjust the temperature of the newly mixed water; a large diameter siphon hose; a couple of new plastic buckets that hold 3-5 gallons.

Use a clean plastic bucket to fill up the garbage can with 10, 20 or 30 gallons of water or however much you want to mix up at one time. Add the proper amount of artificial salt mix for that much water, and toss your small, cheap powerhead into the garbage can to stir it up. While it’s mixing, put the submersible heater in to adjust the water temp, and add dechlorinator or detox if using tap water (if using reverse osmosis deionized water, or another softened source, add a pH buffer to the new water). Let the new batch of water mix, aerate, and stabilize for 24-48 hours before you perform the water change and check to make sure the temperature and pH of the new water matches your aquarium.

Checklist of Monthly Chores:

*Clean filters/replace filter pads/rinse and recharge or replace chemical media.
*Perform partial water change.
*If needed, vacuum uppermost layer of substrate (top 1/2 inch).
*Clean aquarium decorations as needed.
*Clean sleeve on the UV sterilizer and check the UV bulb.

Best of luck with your new seahorse setup, Barbara!

Happy Trails!
Pete Giwojna

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