Dear Sue:
Unfortunately, your 10 gallon hex tank is way too small to consider keeping any of the larger breeds of seahorses such as Mustangs or Sunbursts (Hippocampus erectus). Even a single Mustang would be uncomfortable in a tank of that size, and the shallow water depth would make them very susceptible to problems with gas bubble syndrome. The greater seahorses need an aquarium at least 20 inches tall in order to mate comfortably and offer some protection from GBS. And they do best in larger tanks with sufficient water volume to maintain stable conditions and provide an adequate margin for error, which is very important for a beginner.
That means you will need to limit yourself to the miniature breeds of seahorses instead, Sue. For example, a 10-gallon aquarium could support a full colony of Pixies or dwarf seahorses (Hippocampus zosterae), or a group of other small seahorses such as the short-headed seahorse (Hippocampus breviceps) or the closely related H. tuberculatus. These are all miniature seahorses that reach an adult size of about 1.5 inches (in the case of H. zosterae) or about 3 inches in length when fully grown, in the case of H. breviceps or H. tuberculatus, half of which consists of their tails.
I think the dwarf seahorses — your original choice — are probably the best suited for a tank like yours, Sue, so let’s discuss their aquarium requirements and a little more detail.
Pixies or Dwarf Seahorses (Hippocampus zostrae)
The first species you might want to consider are Pixies, which are Ocean Rider’s strain of domesticated dwarf seahorses (H. zosterae). Dwarf seahorses are the smallest of all the cultured seahorses and a whole colony of them can live happily in a 10-gallon aquarium. They are the easiest of all the seahorses to breed and raise, and they are the least expensive ponies, which makes them affordable in groups.
However, three factors make Pixies or dwarf seahorses (H. zosterae) somewhat more demanding to keep than the larger breeds of seahorses such as Mustangs and Sunbursts (Hippocampus erectus):
(1) Their need for live foods.
(2) The small water volume of typical dwarf seahorse setups.
(3) Their susceptibility to aquarium hitchhikers and stinging animals (e.g., hydroids, Aiptasia).
Because of their small size and sedentary lifestyle, dwarf seahorses cannot be consistently trained to eat frozen foods without risking polluting the aquarium with uneaten food. As a result, the adults must be provided with copious amounts of newly-hatched brine shrimp (Artemia nauplii) at least twice a day and the fry must have access to bbs throughout the day.
This means maintaining a battery of brine shrimp hatcheries and hatching out large quantities of brine shrimp on a daily basis. If you are not proficient at hatching out brine shrimp or consider that to be too much of a hassle, then dwarf seahorses are not for you!
Because they are so terribly tiny — adult H. zosterae are only about the size of your thumbnail and half of that is tail — dwarf seahorses do best in small aquaria of 2 to 5 gallons to facilitate maintaining an adequate feeding density of bbs. Such a small volume of water is more susceptible to fluctuations in temperature, pH, and specific gravity than larger aquariums, and the water quality can also go downhill much faster in such small tanks than in large setups.
This means that dwarf seahorse keepers must practice diligent aquarium practices and an accelerated maintenance schedule in order to stay on top of water quality. As an example, water changes should be made weekly or biweekly, rather than monthly or bimonthly. This is not really onerous at all, since the water changes are so small (a fraction of a gallon to 1 or 2 gallons at most, depending on the size of the dwarf tank). It’s an easy matter to prepare and store a month’s worth of freshly mixed saltwater in advance, and I then find that I can perform a water change, vacuum of the bottom of my dwarf seahorse tank, and clean the sponge filters in no more than 5-10 minutes tops. But if the aquarist is not diligent about water changes and aquarium maintenance, dwarf seahorse setups can "crash" more easily than bigger, more stable aquariums with a larger volume of water.
The need for an accelerated maintenance schedule and daily feedings of live foods thus makes dwarf seahorses a bit more demanding to keep than the greater seahorses.
In addition, because of their diminutive dimensions, dwarf seahorses are susceptible to the stings from hydroids and Aiptasia rock anemones, which normally do not present a risk to the larger breeds of seahorses. Hydroids in particular are especially problematic for dwarves because once they find their way into a dwarf seahorse setup or nursery tank, the dreaded droids can explode to plague proportions very quickly because conditions are ideal for their growth: perfect temperatures, an abundance of planktonic prey that is renewed every few hours, and a complete absence of predators. As they proliferate and spread, they will soon begin to take a toll on the seahorse fry and even adult dwarfs can succumb to multiple stings or secondary infections that can set in at the site of a sting (Abbott, 2003).
The type of substrate — aragonite, black sand, crushed shell, coral sand, or a bare glass bottom — doesn’t seem to make much difference at all. It’s just that nursery tanks and dwarf seahorse tanks are perfect environments for culturing hydroids, and once they find their way into such a system they go forth and multiply with a vengeance. So unless dwarf seahorse keepers take special precautions, they can find themselves waging a losing battle with an infestation of hydroids, and that’s something that hobbyists who keep larger seahorses simply never need to be concerned about.
However, dwarf seahorses are widely considered by far the easiest seahorses of all to raise. They are prolific, breed readily in groups, and produce large, benthic fry that accept newly-hatched brine shrimp as their first food and reach maturity in as little as three months. They are the least expensive of all the seahorses to own and a dwarf seahorse aquarium can be set up far more economically than a system for keeping the larger seahorse species.
Dwarf seahorses are therefore ideal for breeders and anyone operating on a shoestring budget. Pint-sized and prolific, these pigmy ponies are the perfect pick for anyone primarily interested in rearing or for any seahorse keepers who can’t afford to devote too much money or space to their hobby. Hippocampus zosterae is the best choice for the novice who wants to learn more about keeping and breeding seahorses before moving on to the big boys. More budding seahorse keepers have cut their teeth on dwarves than all the other seahorses put together. H. zosterae is the right pick for newbies who would like to try their hand with seahorses for a modest investment, or for hobbyists with a tight budget, or aquarists looking for captive-bred seahorses that are a snap to breed and a breeze to raise, or anyone captivated by keeping tiny elfin creatures no bigger than your thumbnail.
All things considered, I feel that the many advantages of keeping dwarf seahorses far outweigh the drawbacks we have outlined above.
Hippocampus breviceps or H. tuberculatus are other miniature breeds that could be kept in a 10-gallon aquarium, if you could obtain them, Sue. They are small enough for a 10-gallon tank and can be trained to eat frozen Mysis, but they are straightly in species that are no longer seen here in the US. Of these minis, only the dwarf seahorses (H. zosterae) are readily available to hobbyists to American hobbyists at this time.
Aside from the dwarf varieties, Sue, you could also consider one pair of Zulu-lulus or Cape seahorses (Hippocampus capensis) for a 10-gallon aquarium providing you equip it with an aquarium chiller in order to maintain cool water temperatures at all times. Zulus are more like Shetland ponies — a bit larger than the miniature species but small enough to be comfortable in a 10-gallon tank that is cool enough for their needs. Zulu’s (H. capensis) are large enough to eat frozen Mysis as their staple everyday diet, so let’s discuss their aquarium requirements in more detail below:
Zulu-lulus (Hippocampus capensis)
Cape seahorses or Zulu-lulus are Ocean Rider’s captive-bred-and-raised strain of domesticated Hippocampus capensis.
Also known as the Knysna Seahorse, Zulu-lulus (Hippocampus capensis) are well suited for beginners. For one thing, these ponies are just the right size for the average home aquarium and are natural born gluttons — the easiest seahorses of all to feed. They are small seahorses, but they have BIG appetites and will eat most anything and everything the giant breeds do. They are aggressive feeders and, in an impressive display of voracity, even small specimens will unhesitatingly tackle large frozen Mysis that may take them two or three snicks to successfully swallow. A hungry Cape seahorse will often have more than half of a large mysid protruding from its snout, making it look like a sword swallower in mid-performance as it gradually works its gargantuan meal down with a series of mighty snicks! It is an amazing sight to watch an undersized capensis choke down several oversized frozen Mysis in quick succession and come hurrying back for more like it was starving with the tail of the last shrimp still sticking out of its mouth! They are capable of remarkable feats of sheer piggery, and everyone marvels at how rotund they are when they get their first good look at well-fed, captive-bred capensis.
Of course, they love frozen Mysis relicta and are accustomed to eating that as their staple diet, but these chow hounds are not at all picky when they put on the ol’ feed bag. These galloping gourmets also eat rotifers, brine shrimp, amphipods, copepods, red feeder shrimp (Halocaridina rubra), Caprellids — you name it and they’ll eat it. All the usual seahorse foods are taken with relish and these seagoing gluttons don’t seem to mind a bit whether they are live, freshly killed or frozen. They normally feed on nonmotile food in the wild (Garrick-Maidment, pers. comm.), so they thrive on frozen food in the aquarium. In short, feeding these fat little fellas is the last thing the hobbyist has to worry about, and they are much easier to feed than the dwarf seahorses which require live foods!
Hippocampus capensis are fat, pudgy little ponies with a very distinctive appearance. Short and stout, with a portly profile, stubby snouts, big bulging eyes, and perfectly smooth bodies — I can’t decide whether these captivating characters are more cute or more comical looking! They are very unusual for seahorses in that they have no semblance of a crest or coronet whatsoever.
These thick-bodied little seahorses are the perfect size for the home aquarium. They reach a total length of just over 4 inches, and are shipped to you at the modest size of 2-3 inches. That makes them around three times the size of dwarf seahorses — small enough to feel right at home in the average aquarium, yet large enough to make fine display specimens and to eat frozen mysid shrimp as their staple diet. Zulus are the ideal size for a 12-gallon nano tank, Brian. They have proven to be very hardy and easy to breed, and when you’re ready for the challenge of rearing, you’ll find newborn H. capensis are relatively easy to raise, much like dwarf seahorse fry.
However, they are temperate seahorses that prefer cooler temperatures than tropical seahorses. The do best at stable temperatures between a range of 70°F-75°F (22°C-24°C) and don’t tolerate temperature spikes above 75°F well at all. That means you will almost certainly require an aquarium chiller to keep your 10-gallon tank tank within the comfort zone for Zulus (H. capensis) at all times, Sue. Without an aquarium chiller, these small water volume in a tank that sides would be subject to overheating during the summertime and to harmful temperature fluctuations year round.
Fortunately, there are some very affordable mini aquarium chillers that could easily be mounted on your 10-gallon setup. For example, the CoolWorks Ice Probe and Microchiller units are ideal for small tanks (10-15 gallons) and will drop the water temperature up to 6-8°F below the ambient room temperature:
Click here: CoolWorks Ice Probe with Power Supply – Marine Depot – Marine and Reef Aquarium Super Store
http://www.marinedepot.com/md_viewItem.asp?idProduct=CW1111
Click here: CoolWorks Microchiller – Marine Depot – Marine and Reef Aquarium Super Store
http://www.marinedepot.com/md_viewItem.asp?idproduct=CW1131
If you equipped your 10-gallon aquarium with such a chiller so it can maintain temperatures in the 70°F-72°F range at all times, it might be a decent set up for a single pair of Zulu-lulus (H. capensis), Sue.
Contact me off list ([email protected]) and I will provide you with lots more information regarding whichever species you feel is best suited for your needs and interests. Just let me know if you are willing to reconsider keeping the dwarf seahorses in your 10-gallon aquarium, and I will provide you with detailed information on preparing an aquarium to meet their needs. Or, if you’re willing to use an aquarium chiller and would like to try the Zulu-lulus instead, shoot me a quick e-mail and I will provide you with loads of information explaining how to optimize your tank for H. capensis instead.
Best wishes with all your fishes, Sue!
Respectfully,
Pete Giwojna
Ocean Rider, Inc. is an Organic Hawaiian-Based Seahorse Aqua-Farm & Aquarium that Follows Strict Good Farming Practices in Raising Seahorses and Other Aquatic Life.
