filtration

Dear hobbyist:

Okay, that sounds like a good plan! The dimensions of your new aquarium look fine and it should have adequate height.

The new Eclipse designs may be better (it’s been sometime since I had an Eclipse tank or hood), but I was not a fan of the older models. As an example of what I’m talking about, those Marineland Eclipse tanks with the top-mounted bio-wheel filter have a few shortcomings that the seahorse keeper must overcome in order for them to be suitable tanks. The main problems with the Marineland tanks are that they have a tendency to overheat, can be somewhat prone to short-circuits due to salt deposits building up on the electronics, and the intake for the filter needs to be screened off to make it safe for seahorses. The bio-wheels can sometimes have a tendency to stop turning.

The heat given off by the enclosed motors tends to get trapped and build up under the hood, so overheating is my biggest concern with the Eclipse hoods. Seahorses in general are vulnerable to heat stress, and the Zulu-lulus (Hippocampus capensis) in particular are sensitive to warm temperatures. They prefer relatively cool water (75°F or lower et al. times), and don’t do well if the water temperature gets to the upper 70s for any length of time. It could be difficult to keep your temperature between 72°F-70 5°F at all times with an Eclipse hood.

In general, I prefer a different type of hood or aquarium cover combined with an external filter or hang-on-the-back filter. The external filter 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 good choices for a standard seahorse setup.

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 (or a spray bar for surface agitation if you decide on a canister filter rather than a hang-on-the-back design).

Regardless of what type and/or model filter you get, it’s an excellent idea to install an efficient protein skimmer on your seahorse tank as well. 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.

As long as you can keep the aquarium temperature around 72°F, Mustangs (Hippocampus erectus) and Zulus (H. capensis) should do well together. I would be inclined to establish the Zulu-lulus in your aquarium first, simply because they are smaller seahorses than the Mustangs. So it may be a good idea to give the Zulus a little head start and allow them to adjust to their surroundings and grow out a little before you introduce the larger Mustangs. I don’t anticipate any sort of conflict at all between the two species, but it should help assure that things go smoothly if the Zulus are the established residents when you add the larger ‘stangs.

Best of luck with your new seahorse setup, sir!

Happy Trails!
Pete Giwojna