You’re very welcome!
Now, with regard to your dilemma for cycling the aquarium, you are on the right track — you do need to add a source of ammonia in order to feed the beneficial nitrifying bacteria that carry out the biological filtration. And the metabolic wastes produced by black mollies or sailfin mollies that had been adapted to full strength saltwater is certainly one way that this could be accomplished. You would want to remove the mollies before you added the dwarf seahorses, however, since dwarf seahorses are too small to swallow even newborn mollies, but the mollies would relish feeding on newborn dwarf seahorses.
However, an easier and more humane way to cycle your new aquarium would be to add a piece of cocktail shrimp to the aquarium, which will produce ammonia as it decays in order to feed the beneficial nitrifying bacteria. For a small tank like yours, all you would need is a piece of raw shrimp (or similar biomass) about the size of your thumbnail to start. It normally takes anywhere from 3-6 weeks to cycle a new aquarium from scratch this way, and using your test kits to monitor the level of ammonia, nitrite, and nitrate will allow you to determine how far along the cycling process has progressed.
For example, Tarma, this is what I normally advise home hobbyists when it comes to cycling a new seahorse setup:
Cycling the Aquarium
Once you’ve rounded up the aquarium, equipment, and accessories you need, your next task is to prepare the new 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 break down 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 nitrate 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 macroalgae periodically, and practicing good aquarium management.
Step-By-Step Instructions for Cycling a New Marine Aquarium
1) Set up the aquarium in the proper location, fill it with freshwater, and operate all of the equipment to make sure everything is working properly with no leaks.
2) Add the artificial salt mix and adjust the salinity (i.e., specific gravity) and pH of the aquarium water to the proper levels.
3) Add the substrate (e.g., live sand and/or live rock) and seed the aquarium with beneficial nitrifying bacteria.
4) Provide a source of ammonia to feed the beneficial nitrifying bacteria and encourage a large population of Nitrosomonas and Nitrobacter to develop in the aquarium.
5) Test the ammonia, nitrite, and nitrate levels regularly to monitor the cycling process and determine when the aquarium has cycled and the biological filtration is fully established.
To make everything crystal clear, we’ll go over each of these steps in more detail below.
First Step: Set up the aquarium in the proper location, fill it with freshwater, and operate all of the equipment to make sure everything is working properly with no leaks.
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 correctly without any leaks or unforeseen problems.
If possible, I recommend using reverse osmosis/deionized water (RO/DI) to fill the aquarium initially and for making regular water changes once the aquarium has been established. RO/DI water obtained from a good source is ultra-pure and using it to fill the tank will help prevent nuisance algae from ever getting started in the newly established aquarium.
If you do not have an RO/DI unit of your own, you can always purchase the reverse osmosis/deinonized water (RO/DI) instead. Most well-stocked pet shops that handle marine fish sell RO/DI water as a service for their customers for between 25 and 50 cents a gallon. If your local fish store (LFS) does not, WalMart sells RO/DI water by the gallon for around 60 cents, and you should be able to find a Wal-Mart nearby. (Heck, even my drug store sells RO/DI water nowadays.)
However, it’s not always safe to assume that RO/DI water purchased from your LFS or your drugstore or some other convenient source is as pure as you might expect. If the merchants selling the RO/DI water are not diligent about monitoring their water quality and changing out the membranes promptly when needed, then the water they provide will not be a good quality and will not produce the desired results. I suggest that you look for an aquarium store that maintains beautiful reef systems on the premises — that’s a good sign that they know their stuff and are maintaining optimum water quality at all times, so the RO/DI water they provide should be up to snuff.
If you do not have access to a good source of reliable RO/DI water, then detoxified tap water will have to suffice for filling your new aquarium. In many areas, the municipal water supply has undesirable levels of amines, phosphates or nitrates, and in the United States, it is always chlorinated and fluoridated, so be sure to dechlorinate/detoxify the water using one of the many commercially unavailable aquarium products designed for that purpose when you add it to the aquarium.
Second Step: Add the artificial salt mix and adjust the salinity (i.e., specific gravity) and pH of the aquarium water to the proper levels.
Once assured that everything’s operating properly and there are no leaks in your aquarium system, go ahead and add the artificial salt mix and adjust the specific gravity and pH. Instant Ocean artificial salt mix is economical and works very well for seahorses. Add enough of the Instant Ocean to raise the specific gravity to between 1.022-1.025 initially.
A specific gravity of 1.024-1.025 is optimum for your most seahorses, so check it with your hydrometer and adjust the specific gravity accordingly. If it’s too low, add more of the Instant Ocean artificial salt mix to raise it up a bit. Allow sufficient time for the new salt to dissolve, and then check the specific gravity again. If the specific gravity is higher than desired, just add more freshwater to dilute it until it drops to the proper level.
Next, test the pH of the aquarium water and adjust it to anywhere between 8.0-8.4. If you used ordinary tap water to fill the aquarium, the Instant Ocean salt mix will often raise the pH to the proper level all by itself. However, if you used RO/DI water or another softened source to fill the aquarium initially, the pH will likely be too low at first. Water purified by such methods is very soft and must usually be buffered in order to establish the proper pH and maintain the total alkalinity and carbonate hardness of the aquarium water at the proper level.
To raise your pH to the proper range (8.0-8.4), just obtain one of the commercially made products designed to adjust the pH upwards in saltwater aquariums and use it according to the instructions. Such a product should be available from any good LFS that handles marine fishes and invertebrates; they typically include sodium bicarbonate as their primary active ingredient and are often marketed under names such as "pH Up" or something similar. If you wish, ordinary baking soda (bicarbonate) from your kitchen will work just as well for elevating the pH.
In the unlikely event that the pH of the aquarium water is too high, it can be dropped using one of the pH-lowering products from your local fish store. However, many of these products use phosphate-based chemicals to lower the pH, and this is undesirable since the phosphates can fuel the growth of nuisance algae. A better way to lower the pH is by adding RO/DI water until it comes down to the proper level.
At this point, a pH that is anywhere between 8.0-8.4 is just fine. The aquarium will cycle faster if the proper pH is maintained, but we won’t worry about fine-tuning the pH until after the aquarium has completely cycled. In fact, once you have adjusted the aquarium pH between this range initially, you don’t need to check it again until after the cycling process is complete and the biological filtration is fully established.
As a rule, we don’t worry about maintaining the pH in the proper range in a new aquarium that is still in the process of cycling because the ammonia and nitrite spikes that occur during cycling will alter the pH. But if the pH should fall to 5.5 or below, the beneficial Nitrosomonas bacteria will begin to decline and die off, disrupting the cycling process, so it’s important to avoid excessively low pH (acidic) readings while the new tank completes the nitrogen cycle.
After you have adjusted the salinity and pH of the aquarium water to the proper levels, leave everything running continuously for at least a few days, 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. This will make sure that the specific gravity and pH have stabilized and that the aquarium equipment is operating properly before you proceed.
Third Step: When the pH and specific gravity of the aquarium water are at the proper levels, and the tank has had time to settle in, you can go ahead and add the substrate (e.g., live sand and/or live rock) and seed the aquarium with beneficial nitrifying bacteria.
Remember, the live sand and rockwork will displace a considerable bulk of the saltwater, and you don’t want the aquarium to overflow when they are added. To prevent this, you will have to turn off the pumps and filters temporarily, remove some of the salt water from the aquarium (a volume of water that’s approximately equal to the amount of water the substrate and rocks will displace), and then add the live sand or substrate, positioning the rockwork to form attractive arrangements that are securely anchored by the way they fit together, rather than feeling rickety or unstable. Ledges, overhangs, and caves will offer shelter and interest to your aquascaping, but be careful to make sure that the live rock is stable and resting securely in place so that there is no danger of collapses or the rock shifting unexpectedly. (Save the excess saltwater that you have removed to allow for the live sand and live rock — it’s clean, freshly mixed saltwater that you can use for making partial water changes at a later date.)
If you have artificial decorations such as synthetic plants or fake corals, and they can also be added to the aquarium at this time (or anytime thereafter).
Once the sand, rockwork, and decorations are in place, top off the tank with some of the saltwater you removed to adjust the water level to the proper point, and then restart the pumps and filters. Don’t be alarmed if the aquarium turns a bit murky or cloudy when the live sand or substrate is added. It’s normal for some fine sediments and particulate matter to be stirred up and released when you’re adding the rockwork and live sand, but the aquarium should clear gradually over the next several days all on its own as these particles settle out or are removed by the mechanical filtration in the aquarium.
If you are using either live rock or live sand, as I recommend, it will contain all the bacteria needed to seed the tank. I suggest a thin layer of live aragonite sand no deeper than an inch or so.
If you are not using live rock or live sand, you can seed the aquarium with nitrifying bacteria by adding a live culture product such as marine BioSpira to help kickstart the cycling process instead. Or, as an alternative, some hobbyists will simply add a handful of gravel or filter media from an already established marine aquarium to seed a new tank with beneficial bacteria, but if this is done, you must be sure to harvest the material you use for seeding from an aquarium you know to be healthy. You don’t want to risk introducing pathogens or parasites to your new aquarium by adding seed material from a tank that has lost fish or had disease problems of any kind. (Do NOT bring home filter material or sand or gravel from an aquarium at your local fish store to provide seed bacteria!)
Fourth Step: Provide a source of ammonia to feed the beneficial nitrifying bacteria and encourage a large population of Nitrosomonas and Nitrobacter to develop in the aquarium.
Once the aquarium has been seeded with beneficial nitrifying bacteria, it is necessary to feed that bacteria with ammonia so that the population of good bacteria can grow and thrive. Unless you are feeding your biofilter with a source of ammonia, you will see no readings for ammonia or nitrite or nitrate in the new aquarium, but it will not yet have even begun to cycle. Nitrite only appears if there is sufficient ammonia in the aquarium to support a population of Nitrosomonas bacteria that live off the ammonia and convert it to nitrite in the process. Likewise, nitrates only begin to accumulate in the aquarium when there is enough nitrite to support a colony of the Nitrobacter bacteria that feed on the nitrite and break it down into nitrate. If there is no ammonia in the aquarium to begin with, this process can never get started and the nitrite and nitrate levels will remain at zero, along with the missing ammonia, even though the tank has no biological filtration ability whatsoever as of yet.
There are a number of different ways to feed the aquarium with ammonia so cycling can proceed. For instance, if you are using live rock that has not been well cured, there will often be a significant die off of sessile organisms from the rock itself, and this die off is typically sufficient to provide ammonia during the cycling process. However, nowadays the live rock available at your local fish store has often been completely cured beforehand, in which case there may not be enough of a die off to sustain a healthy population of nitrifying bacteria. In that case, you’ll need to add another source of ammonia besides the dying organisms on and within the live rock itself.
Other popular methods for providing a source of ammonia include the fishless cycling process, 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.
And there is always the possibility that the damsels or mollies could be carrying disease, and it would be a shame to introduce pathogens or parasites into a new aquarium by using such expendable fish to cycle the tank. The damsels or mollies are likely to be stressed by the high ammonia and nitrite levels during the cycling process, which leaves them susceptible to disease, and we don’t want to put our seahorses at risk simply because of the way we cycled their aquarium.
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. Depending on the size of the aquarium, I like to use a piece or two 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 fuel the cycling process.
The only drawback to this method of cycling is that it can sometimes produce an objectionable odor nearby the aquarium as the cocktail shrimp/prawn decomposes. Most times this just produces a slight "fishy" odor, but sometimes, in the advanced stages of decay, the odor of putrefaction can also become quite noticeable. Fortunately, the odor will begin to dissipate quickly as the population of Nitrosomonas bacteria that feed on the ammonia begin to convert it to nitrite. If it gets to the point where it’s driving your wife and kids out of the house and mutiny is in the air, then you may have added too much shrimp and you should remove a portion of the decaying biomass.
IMPORTANT: Do not operate your protein skimmer, ultraviolet sterilizer, or ozonizer, or make water changes while your new aquarium is cycling. Remove chemical filtration media while the aquarium is cycling and avoid adding any ammonia-removing liquids or ammonia-sequestering products (such as BIO-Safe, Amquel, Ammo-lock, Aqua-Safe, etc.) while the tank cycles. You want a nice high ammonia spike (within reason), followed by a nice high nitrite spike, when the aquarium cycles in order to build up the largest possible population of the nitrifying bacteria that feed on ammonia and nitrite, so using any type of filtration or additives that could reduce the amount of ammonia or nitrite at this time will actually hinder the cycling process and be very counterproductive.
Fifth Step: Test the ammonia, nitrite, and nitrate levels regularly to monitor the cycling process and determine when the aquarium has cycled and the biological filtration is fully established.
Now that you have seeded the new aquarium with beneficial bacteria and provided a source of ammonia to feed that bacteria, all you need to do is to wait for a sufficient population of the desirable bacteria to build up in the aquarium. By using your test kits for ammonia and nitrite regularly (daily) at this time, you can monitor the cycling process and keep track of how everything is progressing.
For example, about 3 days after you add the cocktail shrimp (or expendable fish, if you go that route), you should 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. A sharp rise in the ammonia level is desirable at this point providing it does not go above 4 ppm (an ammonia level above 5.0 ppm can actually become counterproductive and prolong the cycling process.) A rise to 1-2 ppm is plenty, but the more live rock an aquarium has, the lower the initial ammonia spike will be, due to the built-in biological filtration ability of the live rock. If for some reason your ammonia does not rise significantly initially, you can always add another piece of shrimp to produce a bigger spike and make it easier to follow the cycling process.
The byproduct of ammonia is nitrite, and during the initial stage of the cycling process, as the ammonia falls, you will normally 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.
[Note: Live sand and well-cured live rock both harbor a significant amount of beneficial nitrifying bacteria and can therefore provide a new aquarium with some "instant" biological filtration ability. Thus, if your newly established aquarium includes live sand and plenty of live rock, you may never see a significant spike in the ammonia and/or nitrite levels. That’s good news, since it means the cycling process is already well underway and that you won’t have to wait much longer before you can begin adding specimens to the aquarium, but it does make monitoring the cycling process a bit more challenging, since you cannot observe the orderly rise in ammonia, following by a decrease in ammonia and a rise in the nitrate level, and finally a drop in the nitrite level accompanied by the appearance of nitrates. Just remember if your aquarium has lots of live rock and live sand and does not show an appreciable spike in the ammonia (or nitrate) level even though there is decaying shrimp or another source of ammonia in the tank, that’s an excellent indication that the cycling process is already nearing completion. As soon as both the ammonia and nitrite levels remain at zero and nitrate begins to appear, it’s safe to add the cleanup crew to such an aquarium.]
For more information about cycling an aquarium using live rock, see the following online article by Karen Barbour:
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. (It typically takes longer for the population of beneficial Nitrobacter to build up than it did for the Nitrosomonas bacteria to peak, so be patient when waiting for the nitrite readings to begin to decrease.) 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.
IMPORTANT: Do not stop feeding your aquarium with ammonia after the nitrite and ammonia readings have both dropped to zero. You need to continue feeding the beneficial nitrifying bacteria in your biofilter with ammonia or they will begin to starve and die off, reducing the biological filtration ability of the aquarium and thereby reducing the amount of life it can support. Continue to add ammonia in the form of the decaying shrimp or expendable fish right up until you add the first seahorses. (Once you add the seahorses and begin feeding them with frozen Mysis regularly, their wastes will provide the ammonia from that moment on.)
Once both the ammonia and nitrite levels in the aquarium have dropped to zero and nitrates have begun to accumulate, you can doublecheck the specific gravity and pH of the aquarium, adjusting them if necessary to make sure they remain at the desired level. It is now safe to add your chemical filtration media, and you can begin stocking the aquarium by adding live macroalgae and your cleanup crew of sanitation engineers.
To be extra safe, many hobbyists like to wait an additional six weeks after introducing the macroalgae and cleanup crew before they acclimate the first seahorses to their new systems. This gives the new aquarium a chance to further break in and stabilize, and also serves as a quarantine period for the aquarium janitors and live plants. Any parasites they may possibly have been carrying that could pose a risk to the seahorses would require a vertebrate host in order to survive, and after six weeks without any fish in the aquarium, any such parasites should have been eliminated and are no longer a cause for concern.
If you are still unsure about how to begin cycling your new aquarium, check out the following online article by Bob Fenner titled "Establishing Biological Cycling & Filtration in Marine Systems," which is available at the following URL. It should answer any remaining questions you may have:
Okay, Tarma, that’s the quick rundown on cycling a new marine aquarium. As you can see, you normally do not want to add your cleanup crew to the aquarium until after it has cycled completely, because the spike in the ammonia and nitrate levels is often fatal to invertebrates such as snails. So wait until the aquarium has completely cycled before you add more snails as aquarium janitors, and everything should go smoothly.
Best of luck cycling your new dwarf seahorse setup!