I want to start a saltwater aquarium

Dear 67:

Okay, I will try my best to clear up some of the confusion and point you in the right direction so that you can get started with your seahorse project.

First of all, let me just explain that the sort of coarse air bubbles produced by airstones, bubblers, bubble wands, air curtains and other such aquarium decorations are perfectly safe in a seahorse tank under most conditions. However, there are two circumstances in which they can become problematic.

The first of these is when the device or aquarium decoration releases it stream of bubbles in a location where the bubbles might be drawn into the intake for a powerhead or an external power filter, whereupon they can be chopped up into tiny microbubbles by the impeller and then reinjected back into the aquarium under pressure. That’s a circumstance that could possibly result in low-level gas supersaturation of the aquarium water, which in turn can contribute to problems with gas bubble syndrome (GBS) in seahorses.

Just as supersaturation in small, closed-system aquariums is often due to the entraining of air on the intake side of a leaky pump, which then chops the air into fine microbubbles and injects it into the water (Cripe, Kowalski and Phipps, 1999), air bubbles that are drawn into the intake for a powerhead or an external power filter can suffer the same fate. In both instances, water and air are mixed under high pressure and forced into the water column, which can result in low-level gas supersaturation. An air leak in inflowing or recirculating water that enters the tank below the surface can cause the same thing (Cripe, Kowalski and Phipps, 1999).

Likewise, the second occasion in which such air bubbles can be troublesome is also related to GBS and happens when the devices or decorations that produce the bubbles are located exceptionally deep in the aquarium. If the bubbles are released at a depth greater than 30 inches, they could again result in problems with low-level gas supersaturation, which is one of the triggers for GBS in our seagoing stallions.

This happens because airstones, air lifts, bubble wands and the like cause gas to dissolve in water to match the ambient pressure (the current atmospheric pressure) PLUS the pressure of the water column above the stone, and that can result in gas supersaturation of the aquarium water if the water depth is too great. Thus, if they are immersed at depths much greater than 20 inches or so, the pressure of the water column above them may be sufficient to cause low-level gas supersaturation of the water, especially when there is little atmosphere/water interface (Colt & Westers, 1982). For example, Robin Weber found that airstone submerged in reservoirs 3 feet deep produced gas supersaturation at the Monterey Bay Aquarium. The airstones produced supersaturation at a level of about 104%, and the only cases of GBS she has ever observed at the aquarium occurred in the most supersaturated exhibits.

However, the air bubbles produced by airstones and various aquarium decorations are perfectly harmless as long as they are kept relatively shallow, no deeper than 20 inches or so, to be on the safe side, and are positioned in an area of the tank where there is no danger that the bubble stream can be drawn into the intake for a powerhead or an external power filter. In fact, under such circumstances, the stream of air bubbles is actually beneficial and can help to prevent problems with gas supersaturation and GBS by increasing the surface agitation in facilitating efficient gas exchange at the air/water interface.

Furthermore, seahorses often enjoy basking in a stream of coarse air bubbles. They really seem to enjoy the tactile stimulation provided by the gentle barrage of bubbles just as if they were relaxing in their own private Jacuzzi. So keep your airstones and air-generating devices/decorations shallow in located well away from powerheads and external filters, and the coarse air bubbles they produce will be beneficial rather than a cause for concern.

In short, airstones, bubble wands, bubble discs or bubble curtains and the like can be used freely in a seahorse tank if you wish, as long as you use them properly, 67. They will not cause the seahorses any harm as long as you keep them relatively shallow and place them where the bubbles stream will not get sucked up into the intake for a powerhead or power filter. As long as you position the airstone or bubble disc or bubble curtain in the aquarium where there is no danger than any of the bubbles can get sucked up into an external filter or powerhead, then the bubbles they produce are harmless and can provide the aquarium with supplemental aeration and additional surface agitation. In fact, many seahorses like to play in the bubble stream almost as if it was their own personal Jacuzzi bath, so the bubbles can be a good stress reliever and a good source of behavioral enrichment for our ponies.

However, many seahorse keepers prefer to avoid such devices in their tanks simply because if you do use an airstone or bubble disc or bubble curtain in your saltwater aquarium, it is going to require a lot more maintenance in order to keep the tank looking nice. That’s because of the problem with unsightly salt creep, which is the result of the steady accumulation of white salt deposits that will build up on the back, side, and aquarium cover above the water line where the bubbles stream is located. This happens because the bursting bubbles produce a fine spray or mist of saltwater on the glass above the water line of the aquarium, which will then leave salt behind when the thin film of water evaporates.

The salt deposits keep getting bigger and thicker over time, and detract from the appearance of the aquarium. They must be cleaned off regularly in order to keep the tank looking nice, and that requires a lot of elbow grease, since the encrusted salt and crusty salt deposits are difficult to remove and must often be scraped off using a single edged razor blade or something similar.

For this reason, it is often better to use the smallest possible powerhead you can get and then position it at the top of the tank so that it roils the surface of the water, thereby increasing the surface agitation and promoting better oxygenation and gas exchange at the air/water interface, rather than using an airstone or bubble wand or some such device in order to improve the aeration and surface agitation. The small powerhead will accomplish the same thing as the bubblers do providing it is positioned properly so that it’s sort of ripples the surface of the aquarium without causing any splashing, and the small powerheads will therefore not cause any problems with crusty white salt deposits or salt creep.

If you decide to include a small powerhead in your seahorse tank for extra water movement and additional surface agitation, 67, be sure to screen off or shield the intake for the powerhead properly so that it cannot harm the seahorses, as explained in more detail below:

Shielding and Screening of Powerheads for Seahorses

In general, it’s a very good idea for seahorse keepers to take special precautions when using powerheads or internal circulation pumps in a seahorse tank in order to assure that a curious seahorse does not get its tail injured or damaged by the impeller for the powerhead/pump. Basically, this just means that whenever the intake for a powerhead pump is large enough to allow an unsuspecting seahorse to get its tail inside, it’s a good idea to shield or otherwise screen off the intake, regardless of how strong the suction may be, just to be on the safe side. Often this merely involves positioning the powerhead amidst the rockwork or anchoring it in place with the suction cup where there’s no possibility for a seahorse to perch on the powerhead or wrap its tail around the inflow/intake for the unit.

When that’s not possible, you may need to take more elaborate measures in order to screen off the intake from the pump are powerhead to make it safe for the seahorses.

For example, here’s how to proceed when using the Hydor Koralia powerheads, which are relatively safe compared to other types of powerheads. For one thing, since they are not impeller-operated, the intake or suction is fairly weak compared to a normal powerhead, and there is therefore no danger that a curious seahorse will have its tail injured by an impeller. Secondly, the “egg” or basket-like structure that covers the powerhead often offers sufficient protection so that an adult seahorse really cannot injure its tail. For example, the gaps in the Koralia 1 are only 1/8 of an inch wide, which is too small for grown seahorse’s tail to fit to the gaps.

Just to be on the safe side, some seahorse keepers will encase the entire egg for a Koralia powerhead in a veil-like material, especially if they have smaller ponies, as explained below:

“I have a Koralia that works great in my anemone tankI have a Koralia that works great in my anemone tank(no seahorses). Just in case I bought a piece of Tulle (bridal veil material) to cover it. I got the purple tulle that looks just like coraline algae. Just cut it into a square and put it over the Koralia and secure the ends with a zip tie. Think of it like a lollipop wrapper-if the pump is the lollipop the tulle is the wrapper and instead of twisting the paper at the bottom like a lollipop you secure with a zip-tie. I have H. fuscus and H.barbouri and they could definetly hitch on the Koralia (and I have the nano) The pump still works great and nothing can get in it.”

Of course, the Tulle trick will work just as well for screening the intakes of other types of powerheads or circulation pumps as well, and the bridal veil material is not so fine that it will easily get clogged up or impede the flow through the device.

You also had a question about the use of distilled water, 67, and you certainly can use distilled water to mix up new saltwater for your seahorse tank if you have any doubts or concerns about the quality of your tap water. Nowadays, I don’t believe that there should be significant levels of any pathogens in the municipal water supply for any town or city as long providing it is chlorinated and monitored carefully, but you certainly cannot always rely on that, since the quality of the tap water does vary greatly from location to location. Well water can be suspect because it can be contaminated by septic tanks, agricultural runoff, and a host of other sources of pollution. Other times it is not the bacteria or total dissolved solids that are problematic for well water, but the composition of the water itself, which may be heavily mineralized or have high levels of nitrates or phosphates naturally…

If you have any suspicions about your water quality in your area, 67, it wouldn’t hurt for you to try a different water source and see if that produces better results. For example, you could switch to natural seawater only, or switch to using distilled water or RO/DI water from another source instead, and see if that results in superior water quality and helps you to avoid potential problems with high nitrates/phosphates in the proliferation of nuisance algae.

However, one thing you must always keep in mind is that if you are going to change the source of water you are using for the aquariums, you need to do so very gradually in order to avoid stressing the aquarium inhabitants. Here are some of the things to remember if you will be changing from natural seawater to well water, or switching from the municipal water supply to distilled water or RO/DI water, or some such change:

Replacement water should be of the same source as the aquarium, whether it be reverse osmosis (RO), de-ionized (DI), distilled or municipal supply, in order to avoid drastic changes in water chemistry. In cases where one is replacing a tap water-based salt mix with a reverse osmosis-based salt mix, the replacement water should be added slowly over the course of several hours to avoid sending the aquarium inhabitants into osmotic shock. If using municipal water, one should check with the local utility company to find out the composition of that tap water. Water containing high levels of nitrate or phosphate should be avoided, and reverse osmosis or distilled water used in its place.

Now let’s address the confusion over terms such as “captive bred,” “tank-bred,” “tank raised” and the like.

To me, “captive bred” (CB) simply indicates seahorses that are captive bred and raised, meaning their parents are cultured seahorses that were selectively bred at an aquaculture facility specifically for the pet trade and the offspring from that pairing were raised by hand in rearing tanks using state-of-the-art grow-out and maturation protocols and technologies. (For example, Ocean Rider seahorses are captive-bred-and-raised or CB ponies.)

In my opinion, these are the best animals for the hobbyist because they have been born and bred for aquarium conditions for a number of generations and are hardy, highly adaptable seahorses with superior disease resistance, as a result. They will have been trained to eat frozen Mysis as their staple, everyday diet from a very tender age, making them much easier to feed and care for then wild-caught seahorses, pen-raised ponies, or tank-raised seahorses. Because they are reared by hand, they are accustomed to the human presence and quickly come to recognize their keepers as the givers of gourmet delights, becoming real pets in every sense of the word. And because each cohort is raised in close proximity with many other seahorses of similar size and age, they are highly gregarious, social animals that very much appreciate the company of others of their kind.

Nowadays, the designations CB (i.e., captive bred) and TB (i.e., tank bred) are terms that are used pretty much interchangeably by hobbyists and the aquarium industry, but you still have to be wary because to my knowledge there are still no official standards or formally recognized nomenclature within the industry regarding these matters.

For instance, there is a world of difference between the designation “tank-bred” (TB) in the designation “tank raised” (TR), so it is very important for the seahorse keeper not to get confused by those two similar terms. Although “tank-bred” typically means the same thing as captive bred and raised in the current nomenclature, the term “tank raised” means something entirely different and you must be very leery regarding tank-raised (TR) seahorses. With regard to seahorses, the tank-raised designation generally indicates that the parents are wild seahorses; rather than having paired up and bred in the aquarium, tank-raised seahorses are generally the offspring of a gravid male removed from the wild. Once he gives birth, his brood is raised in captivity as usual, but of course his progeny have the same genotype or genetic makeup as wild seahorses, and are therefore no more accustomed to life in the aquarium than seahorses collected from the wild. As a result, they may have difficulty adjusting to aquarium conditions and frozen foods, and they will not have the same disease resistance as seahorses that have been captive-bred-and-raised for many generations.

Further complicating the situation is the advent of seahorses that have been “pen-raised” in the open sea under less than desirable circumstances, and which are now reaching the market in the United States in large numbers. Net Pens are a low-tech, low-maintenance method of farming seahorses that basically involves raising them in large enclosures in coastal waters. It is a common practice in Indonesia, many Asian countries, and the Philippines. In some cases, entire lagoons may be fenced off for that purpose. In the simplest form of pen rearing, broodstock are released into these enclosures, and then they and their progeny are pretty much allowed to fend for themselves thereafter. Any offspring that survive to marketable size are periodically harvested from the holding pens or lagoons.

Such operations are controversial with environmentalists for a number of reasons. Since the enclosures are open to the ocean, there is a real risk that adults or their fry may escape from the pens and establish colonies in the wild that may pose a threat to endemic seahorse populations. The pens are no barrier to disease organisms or parasites, so pathogens and parasites imported on foreign broodstock may spread to fishes in the wild (or vice versa). Wastes from the high density of penned animals are carried directly to ocean on prevailing tides and currents and may have a negative environmental impact on the surrounding area. There is no way to monitor the penned animals, hence no way to determine whether the seahorses they contain are actually born and raised in the enclosures or are merely wild-caught seahorses maintained in holding pens prior to being shipped off to unsuspecting consumers.

Pen-grown ponies can thus be risky for the hobbyist because of the circumstances under which they were raised. In essence, a mesh barrier is all that separates them from wild seahorses. There is no guarantee they will be disease free. Although many of them learn to accept frozen Mysis, there is no guarantee they will eat frozen foods since they are often accustomed to foraging for live prey. There is no guarantee they will be able to adjust to aquarium conditions since they are essentially raised in the sea. There is no guarantee that they are even captive bred, since the pens are not secure and livestock is introduced and removed from the pens and lagoons on a continuous basis. There is no guarantee they will be friendly and sociable rather than shying away from their keepers, since they are unaccustomed to the human presence. Pen-raised ponies are particularly misleading because they are almost never advertised as such — they are typically called captive raised or even captive bred seahorses, which can lead the unwary consumer to assume that they have been painstakingly raised using intensive mariculture techniques and rearing protocols. Nothing could be further from the truth.

Seahorse keepers that are shopping for their livestock at their LFS should therefore proceed with caution nowadays. Don’t assume that the new CITES regulations protecting the genus Hippocampus automatically assures that the seahorses sold at your LFS are cultured animals.

If the seahorses in question are over 4 inches in total length, there is a strong possibility the seahorses were harvested from the wild. It’s a mistake to assume that since CITES regulations to protect the genus Hippocampus went into effect in 2004, all the seahorses now being exported to the US have been captive-bred-and-raised. Plenty of wild-caught seahorses are still entering the country, destined for the pet trade.

The CITES regulations currently use a size limit to manage the seahorse fishery. Seahorses smaller than 10 cm or about 4 inches in length are illegal under CITES and cannot be imported or exported by member nations. However, wild-caught seahorses larger than 4 inches can still be imported legally if the necessary permits are obtained. Also, CITES regulates only the international trade in seahorses, so Hippocampus erectus and Hippocampus zosterae collected in US coastal waters are exempt from the regulations and can still be marketed freely within the US.

So when you purchase seahorses from your LFS there is a good possibility that they may have been procured from the wild or pen-raised rather than born and raised in captivity at an aquaculture facility. It’s fine if you want to give the new seahorses at your LFS a try, but because of the uncertainties surrounding them, be sure to play it safe and quarantine them before introducing them to your main tank, just as if they were wild seahorses. Assume they are wild or at best pen-raised and take all the necessary precautions so you won’t get burned. And I would also be a very sensible precaution to set up a new tank just for them, rather than mingling them with your existing captive bred livestock.

One other thing to bear in mind when you are ready to purchase the livestock for your seahorse tank is that it is very desirable to purchase the animals directly from the breeder, rather than from a wholesaler, online outlet, or retail outlet. Given a choice, it’s always better to eliminate the middlemen and order your seahorses directly from the breeder in order to obtain the healthiest possible livestock. When you obtain your specimens directly from the breeder, you know that they have been fed and handled by seahorse experts from the moment they were born until the moment they are shipped to the hobbyist. You are thus assured that the seahorses will arrive well-fed and in top condition. Seahorses from a High-Health aquaculture facility such as Ocean Rider are certified to be free of pathogens and parasites, and will thus reach you at the peak of health.

That’s may not be the case when seahorses are obtained from a wholesaler, online source, or your LFS. When seahorses are kept at a retail outlet, they are typically held in aquaria that share a common filtration system with all the rest of the tanks in the store. This means that the seahorses may have been exposed to pathogens and/or parasites carried on fishes from all the corners of the globe while they were in the holding tanks at your LFS or the wholesaler be obtained them from, making them potential disease vectors for a wide range of health problems.

In general, if you’re new to seahorse keeping, you will increase your chances for success if you start off with hardy, easy to feed, captive-bred-and-raised livestock you obtained directly from a reputable breeder.

Finally, if these will be your first seahorses, 67, then I would strongly recommend that you read through the Ocean Rider Seahorse Training Program beforehand to assure that you will be well prepared to give your ponies the best possible care when they arrive. The training course is completely free of charge and I would be happy to send you the complete training manual in PDF format as an attachment to an e-mail so that you can download it, save it on your computer, and then read through the material at your leisure from the comfort of your own home.

The training manual is quite comprehensive, consisting of several hundred pages of text and more than 250 full color illustrations, and it will teach you everything you need to know in order to keep seahorses successfully in a home aquarium. It will explain how to optimize your aquariums to create an ideal habitat for the ponies. Reading through the information in the lessons should clarify any remaining questions you may have, and it will assure that you get started off on the right foot. (For example, one of the lessons in the Ocean Rider Seahorse Training Program is devoted entirely to the topic of compatible tankmates, including suitable live corals and invertebrates, as well as other fish that make good companions for seahorses.)

If you would like to examine the free manual for the training program, just send me a brief reply to that effect via e-mail, and I will send you a copy in return. (The seahorse training program is a correspondence course that is conducted entirely via e-mail, so you must first establish e-mail communication before we can proceed with the training.)

You can reach me anytime at the following e-mail address:

[email protected]

Best wishes with all your fishes!

Happy Trails!
Pete Giwojna, Ocean Rider Training Program Advisor