Re:Filter help

Dear Wayne and Lisa:

It sounds like you’re off to a pretty good start already. The 56-gallon aquarium that you have selected should make a fine home for a pair of Mustangs or Sunbursts (Hippocampus erectus) and some compatible colorful invertebrates. 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. So you’re new tank is a very good size to start with and should provide plenty of room for your seahorses to roam and explore.

You have the right idea about reading everything you can get your hands on with regard to saltwater aquariums and seahorses. The best approach is always to do your homework and research as much as you can about marine aquariums and the care and requirements of seahorses before you take the plunge, and I would like to make a couple of suggestions for you to add to your reading list.

There are two books that I highly recommend for all inexperienced marine aquarists. An excellent place to start would be to read the book "The New Marine Aquarium" by Michael Paletta. Next I would suggest you follow that up by perusing "The Conscientious Marine Aquarist: A Commonsense Handbook for Successful Saltwater Hobbyists" by Bob Fenner. Those are both outstanding books for a beginner that will give you an good grasp of the basic things you need to know to maintain a marine aquarium.

After you’ve had a chance to digest The New Marine Aquarium and The Conscientious Marine Aquarist, and have a better understanding of the basic principles involved in keeping a saltwater aquarium, you should next study a good guide book devoted for seahorses. I would say the most useful of these for your needs is "How to Care for your Seahorses in the Marine Aquarium — A Stable Environment For your Seahorse Stable" by Tracy Warland. All of the books I have mentioned should be available from your local library or can be purchased from any of the major booksellers.

There is also one good disease book on seahorses that you might find very useful. Dr. Martin Belli, Marc Lamont, Keith Gentry, and Clare Driscoll have done a terrific job putting together "Working Notes: A Guide to the Diseases of Seahorses." Hobbyists will find the detailed information it contains on seahorse anatomy, the latest disease diagnosis and treatment protocols, and quarantine procedures to be extremely useful and helpful. It has some excellent dissection and necropsy photos as well as a number of photos of seahorses with various health problems. This is one book every seahorse keeper should have in his or her fish-room medicine cabinet, and I highly recommend it! In time of need, it can be a real life saver for your seahorses. It’s available online at the following web site:

Click here: Working notes: a guide to seahorse diseases > books > The Shoppe at Seahorse.org | CafePress

http://www.cafepress.com/seahorses.55655887

There are also a number of interesting articles about seahorses available online that would be helpful for your ongoing research. For example, I wrote an article in Conscientious Aquarist called "Feeding Stations : A Better Way to Feed Seahorses" that you may find useful. It discusses all the different kinds of feeding stations, including natural feeding stations, and explains how to do keep seahorses to use a feeding tray in considerable detail. It’s available online at the following URL:

Click here: Seahorse Feeders
<http://www.wetwebmedia.com/ca/volume_2/cav2i5/seahorse_feeders/seahorse_feeders.htm&gt;

And I know you would enjoy the two-part article on coloration in seahorses that I recently wrote for Conscientious Aquarist online magazine, if you haven’t already seen it. You can read the articles at the following URL’s and enjoy Leslie Leddo’s magnificent photographs:

part one:
<http://www.wetwebmedia.com/ca/volume_4/V4I1/hippocampus_color/Color_In_Hippocampus.htm&gt;

part two:
<http://www.wetwebmedia.com/ca/volume_4/V4I2/hippocampus_color2/Color_In_Hippocampus2.htm&gt;

I sympathize with your confusion regarding the filtration system that would be best for your needs — there are certainly a bewildering array of filtration options available these days. If you’re going to include live rock in your aquarium, it will provide the bulk of the biological filtration you need as well as denitrification to help keep the nitrates nice and low, and you don’t need anything fancy for supplemental filtration at all. In that case, you won’t need an expensive wet/dry trickle filter or an affordable biowheel filter or anything of that nature, which are filters that excel at providing efficient biological filtration.

Rather, a simple external power filter is all you need to provide added water movement and circulation for your aquarium, as well as accommodating any mechanical or chemical filtration you may desire. Nothing fancy is needed here, since it’s primary purpose is to provide adjustable water movement and circulation that can be switched off during feedings if needed.

The type or brand of supplemental filter you choose for your live rock tank is therefore 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 to promote gas exchange at the air/water interface. 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 chemical filtration media such as activated carbon and polyfilter pads. A prefilter is very desirable, as is a "waterfall" return or a spray bar return if you go with a canister filter.

And you will want to filter to be able to turn over the entire volume of the aquarium about five times every hour in order to provide adequate circulation throughout the whole tank. So for a 56-gallon aquarium, you’ll want to an external filter that can pump out around 300 gallons per hour. Or you could use two smaller hang-on-the-back filters whose combined output is about 300 gallons per hour, and position one of them on the far left in one of them on the far right side of the aquarium. That arrangement would provide good cross circulation to eliminate dead spots in the aquarium.

If there is a good local fish store in your area, I suggest you pay them a visit and tell them you have a 56-gallon aquarium that you are setting up for seahorses with live rock for biological filtration, and asked them to recommend a good filter that meets the criteria we discussed above. They can help you find just the right unit with the desirable features I mentioned previously.

In your case, since you only want to keep a pair of Hippocampus erectus and some colorful invertebrates in your 56-gallon aquarium, even an undergravel filter would be quite adequate. So if you wish, your 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 reverse-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.

Again, 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. For this reason, reverse flow undergravels often work best with seahorses; they help prevent detritus from accumulating in the gravel bed.

I recommend biweekly of about 15% or weekly water changes of a least 25% at the very least 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. With just a pair of seahorses in a 56-gallon aquarium, the undergravels should be more than adequate.

The type of filtration you choose ultimately depends on what filtration system you are most comfortable with and how much you can afford to budget for your aquarium system.

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 (1/2" to no more than 1" deep) for the substrate;
(2) as much as 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.

As much as 1-2 pounds of live rock per gallon is recommended if the live rock will be the primary means of biological filtration in the aquarium. That amount of live rock will provide adequate levels of both nitrification and denitrification for the tank. (However, if you will have an additional means of biological filtration on the aquarium, then you won’t be nearly that much live rock and you can get by with a fraction of that amount.) You can simply select the precured live rock you find most attractive at your LFS and add enough of it to create interesting rock formations that are aesthetically pleasing to your eye. Use enough rock to create some interesting caves, arches, ledges and overhangs.

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.

By and large, bristleworms are beneficial scavengers and sand sifters unless their numbers get out of hand, so a good 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 at least 1.045 to 1.050 for several minutes before you introduce it to the aquarium. These saltier the water, the shorter the length of time you need to soak the live rock and the more effective it will be in driving out unwanted hitchhikers. 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 several minutes 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. Several minutes in the hypersalinity is usually 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.

The best way to obtain live rock is from an aquarium store in your area that caters to reef keepers. They will have pre-cured live rock available and you can handpick interesting rock formations that are heavily infested with pinkish-purple coralline algae for your aquarium. That will also save you the cost of having the live rock shipped to you, which can be considerable because of the weight of the rocks.

Aquarium Substrate

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.

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) 3-6 inches deep 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.

The type of sand I usually prefer for this is Nature’s Ocean Bio-Activ Live Aragonite Black Beach sand. A thin layer of the sand should make the ideal substrate for your aquarium, and you can order it online from the following site:

http://www.naturesocean.com/live_sand.htm

Otherwise, either the Arag-Alive Indo-Pacific Black Sand by CaribSea or else the CaribSea Tropical Isle Tahitian Moon Black Sand would be good alternatives. You can obtain them online from Premium Aquatics and a number of other sources, and either of them should also work well for the substrate in a seahorse tank.

Here is a simple itemized list of the equipment and accessories you would need for such a setup, Wayne and Lisa. Unless they are listed as optional, you will need to line up the following items, if you don’t already have them.

1) A suitable aquarium of at least 30 gallons (the taller, the better).
2) Glass Cover or hood for the aquarium.
3) Strip reflector or light fixture to fit the new aquarium.
4) Florescent bulb(s) for the strip reflector or light fixture.
5) External filter to provide water movement and supplemental filtration.
6) Titanium grounding probe to protect against stray voltage.
7) A quality protein skimmer (optional but highly recommended).
8) Ultraviolet Sterilizer (necessary for wild-caught seahorses but not needed for Ocean Riders).
9) A thin layer of live sand (1/2" to no more than 1" deep) for the substrate.
10) Well-cured live rock.
11) Hydrometer for checking specific gravity or salinity.
12) Saltwater test kits for measuring the following aquarium parameters:
ammonia
nitrite
nitrate
pH
dissolved oxygen (optional but highly recommended)
13) Aquarium thermometer.
14) Instant Ocean artificial salt mix
15) Natural or Artificial Hitching Posts
16) Package of Frozen Mysis to feed the seahorses (e.g., Piscine Energetics, Hikari and Gamma are all good brands to choose from).

For best results with Hippocampus erectus, when you set up the aquarium strive to maintain stable water conditions within the following aquarium parameters at all times:

Temperature = optimum 72°F-75°F (22°C-24°C).
Specific Gravity = range 1.022 – 1.026; optimum 1.0245
pH = range 8.0 – 8.4; optimum ~8.2
Ammonia = 0
Nitrite = 0
Nitrate = range 0-20 ppm; optimum 0-10 ppm

Protein Skimming.

Although seahorses can certainly be kept successfully without the use of a protein skimmer, I recommend including a good skimmer for best results. As a rule, seahorses are messy feeders, particularly when scarfing down enriched frozen Mysis. Ample evidence of this is revealed every time they scarf one up. As they snick up a shrimp with their slurp-gun snouts, water is passed over their gills and expelled forcibly (it is this very process that generates the powerful suction they use to slurp up their prey). As the jet of water is ejected through their gills, it carries a cloud of macerated particles and debris with it. It is a startling sight the first time you observe this phenomenon, for it brings a fire-breathing dragon to mind. As one young hobbyist matter-of-factly described it, "My seahorse blows smoke out of its ears when he eats." I’ll be darned if that’s not exactly what it looks like, too!

The majority of the undesirable metabolites, organic wastes and excess nutrients that accumulate in our aquariums and degrade water quality are "surface-active," meaning they are attracted to and collect near the surface of a gas-liquid interface (Fenner, 2003). Skimmers take advantage of this fact by using a column of very fine air bubbles mixed with aquarium water to trap dissolved organics and remove them from our systems. This air-water mixture is lighter than the surrounding aquarium and rises up the column of the skimmer until the foam eventually spills into a special collection cup atop the skimmer, which can be removed and emptied as needed. Proteins and other organic molecules, waste products, uneaten food and excess nutrients, and a host of other undesirable compounds stick to the surface of the bubbles and are carried away along with the foam and removed from the aquarium (Fenner, 2003a). As a result of this process, these purification devices are typically known as foam separators, foam fractionators, air-strippers, or simply protein skimmers.

In my experience, nothing improves water quality like a good protein skimmer. They provides many benefits for a seahorse setup, including efficient nutrient export, reducing the effective bioload, and increasing both the Redox potential and dissolved oxygen levels in the water (Fenner, 2003a). They do a tremendous job of removing excess organics from the aquarium, including phenols, albumin, dissolved organic acids, and chromophoric (color causing) compounds (Fenner, 2003a). Their ability to remove dissolved wastes BEFORE they have a chance to break down and degrade water quality makes them indispensable for controlling nuisance algae. A good protein skimmer is an invaluable piece of equipment for keeping your nitrates low and your water quality high when feeding a whole herd of these sloppy eaters in a closed-system aquarium.

When it comes to skimmers, both the AquaC Remora and Euro-Reef series of protein skimmers are first-rate units that will serve you well. You can’t go far wrong if you select a quality AquaC or Euro-Reef skimmer rated for an aquarium of at least 40 gallons. I’ve also heard good things about the H.O.T protein skimmers. I believe Premium Aquatics (http://www.premiumaquatics.com) carries all of those brands of hang-on-the-back protein skimmers, and I would select one of the above if I was you.

If space is at a premium as far as installing a protein skimmer goes, a lot of hobbyists like the Red Sea Prizm protein skimmers because of their sleek compact design.

Okay, Wayne and Lisa, that’s the quick rundown on the main items you are going to need in order to get your new 56-gallon seahorse tank up and running. If you contact me off list ([email protected]), I will be happy to provide you with a lot more information on the care and keeping of Hippocampus erectus, as well as detailed instructions for optimizing your new aquarium to create an ideal environment for Mustangs or Sunbursts.

Best of luck with your continuing education and research into the marine aquarium hobby!

Happy Trails!
Pete Giwojna