Honest advice on tangs

Dear Nova:

Tangs or surgeonfish are sometimes doable in a seahorse tank, but you MUST have a large enough aquarium, quarantine the tang rigorously before hand, and take special care to feed both the surgeonfish and the seahorses properly. This is what I normally advise seahorse keepers with regards to tangs:

Tangs and Seahorses

As algae eaters, tangs or surgeonfish in general are considered to be reef safe and may also be considered for a seahorse tank under the right conditions. If the aquarium is large enough, and you are willing to target feed the seahorses to assure that they get their fair share at feeding time, and you carefully quarantine them first, then you may safely consider adding some blue tangs (Paracanthurus hepatus) or small yellow tangs (Zebrasoma flavescens), as discussed below:

It’s usually best to avoid otherwise docile tankmate for seahorses if they are aggressive feeders that could out-compete them for food. However, I find that such concerns are generally unwarranted when it comes to hardy captive-bred-and-raised seahorses that eat frozen foods. In the bad old days of seahorse keeping, when delicate wild seahorses were the only option, it was indeed absolutely imperative to avoid keeping active fishes that were greedy eaters with wild-caught seahorses that were dependent on live foods. It was difficult enough to come up with sufficient live food for the seahorses in the first place, and active fishes would greedily dart around the tank and busily scarf up all the live food before the horses got much more than a taste. But that is no longer the case with Ocean Rider seahorses, and the feeding habits of potential tankmates need no longer be an overriding concern (Delbeek, Oct. 2001).

Although competition for food is always an issue with seahorses, in my opinion, it is no longer sufficient reason to automatically exclude entire categories of fishes as potential tankmates. There’s no denying that Longnose Hawkfish (Oxycirrhites typus), for example, are active feeders; they will definitely love the taste of frozen mysis and can complicate feeding your seahorses. Same with your clownfish and Cardinalfish. But there are ways around that…

For instance, the same thing is true with regard to pipefish and decorative shrimp, yet no one disputes that they make splendid companions for seahorses. Nowadays, almost every seahorse setup includes a few Peppermint Shrimp (Lysmata wurdemanni), Scarlet Cleaner Shrimp (Lysmata amboinensis), or Fire Shrimp (Lysmata debelius). They are popular additions to a seahorse tank because hobbyists like to use them to augment their cleanup crews and add a splash of color and activity to their tanks. Aside from their utility as attractive scavengers, they often perform a useful service by grooming the seahorses, which is fascinating to watch, and regularly reproduce, releasing swarms of nauplii many seahorses love to eat. Peppermint Shrimp are especially popular because they are natural predators of Aiptasia rock anemones and do a wonderful job of eradicating these pests from the aquarium.

Yet once established in the aquarium, those beautiful red shrimp species are much more active feeders than seahorses. They’ll come flying across the tank the moment that enticing scent of frozen mysids hits the water, raiding the feeding station and snatching mysis right out of the ‘horse’s snouts. Does that mean they’re incompatible with seahorses? Heck no, you just shoo the pesky shrimp out of the way at dinnertime and target feed the seahorses, making sure each of them gets its fill. Well, a Longnose Hawk is no more of an aggressive feeder than the ever-popular cleaner shrimp are, and no more difficult to deal with than the mischievous shrimp at feeding time.

For captive-bred seahorses, which eat enriched frozen mysis as their staple diet, it is customary to feed the more active fish and inverts their fill of standard aquarium foods first, and then target feed the seahorses with frozen mysis, using the feeding wand or baster to discourage any fishes that might try to steal a bite while the seahorses are eating (Delbeek, Oct. 2001). This works quite well providing the fishes are suitable tankmates for seahorses.

That’s SOP for many seahorse keepers and is not much different than the situation in a species tank when one of your seahorses is an aggressive eater with an insatiable appetite that tends to monopolize the feeding station, and one of your other seahorses is a deliberate feeder that has to examine every morsel of mysis forever before he finally eats it. Hardly an insurmountable problem.

Aquarists that are accustomed to catering to the demands of delicate wild-caught seahorses routinely exclude all butterflies, tangs and wrasses as a matter of course, and rightly so. But as long as your tank is big enough, such precautions are no longer strictly necessary when it comes to farm-raised seahorses that are born and bred for life in the aquarium. For example, here’s an example of such a mixed community that’s proven to be very successful for a home hobbyist:

“My tank is a 150 gallon tall (3 1/2 feet) with a 50 gallon sump system giving me 200 gallon volume of water!! a good amount of live rock (approximately 125 pounds)! I use Aragonite sugar sized oolitic sand. For filtration and circulation I use a Rio 3500 with a backpack overflow and I have a protein skimmer, UV sterilizer, two sponge filters, a magnum 350, an emperor 400 and I use purigen — NO carbon.

I house approximately 30 sea horses along with a lot of snails both turbo grazers and Nassarius for detritus! I keep two scooter blennies, several wrasses, 3 butterfly fish, and a naso and kole tang! I also have 3 clowns. Usually you don’t see sea horses in a tank with fish and normally this might be a problem! However, I have ONLY … captive raised sea horses and they were in the tank first and I decided to try the fish with a second tank cycled and in the wings to move the fish to should it have been an issue! Well the … horses were not ill effected at all — in fact the truth be told the sea horses were somewhat bullish with the fish (Susan, 2003).”

I’ve said it before and I’ll say it again: wild-caught seahorses and their captive-bred counterparts are very different animals. These differences extend to the types of fishes that make satisfactory tankmates for each. The feeding habits of farm-raised seahorses make it possible to keep them with fishes that would be absolutely out of the question for wild horses.

So if your seahorse tank is large enough, then you might consider adding a small yellow tang (Zebrasoma flavescens) or small blue tang (Paracanthurus hepatus), providing you observe the usual precautions. The Regal Blue Tang (P. hepatus) is one of my favorite reef fish and has aptly been described as "the bluest thing on earth," and the ubiquitous yellow tang (Z. flavescens) is probably the most widely kept of all the tangs. Here are some things to keep in mind if you decide to give a tang a try.

First of all, both species (and tangs in general) be a little delicate and are prone to marine ich (Cryptocaryon irritans) and other maladies during the stressful period when they are adjusting to a new aquarium, particularly if they were not fed properly while making the rounds from collector to wholesaler to retailer to hobbyist. Once a tang becomes malnourished and develops a pinched belly, it has been my experience that they almost never recover. So when selecting specimens from your LFS, look for well fed individuals that are producing fecal pellets.

As you know, tangs are herbivores that require a high percentage of plant matter in their diet. In order to thrive, they need their veggies and lots of them on a daily basis. If you have only been feeding your tangs once or twice a day along with your seahorses and the rest of your fish, that’s not adequate to sustain them over the long term. In order to stay in good condition, they need to have vegetable matter constantly available to them so they can graze on it throughout the day.

Of course, they love to chow down on macroalgae, but the most convenient and economical way to provide them with their veggies is to keep sheet algae available for them on a lettuce clip so they can graze on it all day long. It was a good idea for you to invest in a diet designed for tangs, but you will find that the sheet algae is a relatively inexpensive alternative that works very well. Obtain several different kinds — green, red, and brown — and alternate which ones you keep in the lettuce clip. Replenish the sheet algae in the lettuce clip as needed throughout the day.

Be sure to carefully quarantine the tang before hand. I would suggest setting up a hospital tank at a specific gravity of 1.010, handpicking a healthy well fed specimen, and quarantining it for four weeks under hyposalinity before you introduce it to your community tank. During the quarantine period, you can fatten up the tang with lots of sheet algae and treat it prophylactically with praziquantel or metronidazole. That will assure that the new tang is free of internal and external parasites and is in top condition when you add it to your seahorse tank. When the quarantine period is at its end, very gradually raise the salinity in the hospital tank to match the specific gravity in your main tank, and then transfer the fish to your community tank as usual. I would take a full week to gradually adjust the salinity upwards again in order to avoid any possibility of dehydrating the fish.

Finally, you’re going to need to target feed the seahorses if you intend to try and active fish like a tang as a tankmates. Here are some pointers in that regard:

Feeding Seahorses

When keeping seahorses in an appropriately elaborate environment, it is imperative that you feed them properly! Domesticated seahorses thrive on enriched frozen Mysis as their staple, everyday diet. But the worst thing you can do when feeding the seahorses in a intricate reef or live rock environment is to scatter a handful of frozen Mysis throughout the tank to be dispersed by the currents and hope that the hungry horses can track it all down. Inevitably some of the frozen food will be swept away and lodge in isolated nooks and crannies where the seahorses cannot get it (Giwojna, 2005). There it will begin to decompose and degrade the water quality, which is why ammonia spikes are common after a heavy feeding. Or it may be wafted out into the open again later on and eaten after it has begun to spoil. Either outcome can have dire consequences (Giwojna, 2005).

The best way to avoid such problems is to target feed your seahorses or set up a feeding station for them. See my online article in Conscientious Aquarist for a detailed discussion explaining exactly how to set up a feeding station and train your seahorses to use it:

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

Personally, I prefer to target feed my seahorses instead. The individual personalities of seahorses naturally extend to their feeding habits. Some are aggressive feeders that will boldly snatch food from your fingers, while some are shy and secretive, feeding only when they think they’re not being observed. Some like to slurp up Mysis while it’s swirling through the water column, and some will only take Mysis off the bottom of the tank. Some are voracious pigs that greedily scarf up everything in sight, and some are slow, deliberate feeders that painstakingly examine every morsel of Mysis before they accept or reject it. Some eat like horses and some eat like birds. So how does the seahorse keeper make sure all his charges are getting enough to eat at mealtime? How does the hobbyist keep the aggressive eaters from gobbling up all the mouth-watering Mysis before the slower feeders get their fair share? And how can you keep active fishes and inverts with seahorses without the faster fishes gobbling up all the goodies before the slowpoke seahorses can grab a mouthful (Giwojna, unpublished)?

Target feeding is the answer. Target feeding just means offering a single piece of Mysis to one particular seahorse, and then watching to see whether or not the ‘horse you targeted actually eats the shrimp. Feeding each of your seahorses in turn that way makes it easy to keep track of exactly how much each of your specimens is eating (Giwojna, unpublished).

There are many different ways to target feed seahorses. Most methods involve using a long utensil of some sort to wave the Mysis temptingly in front of the chosen seahorse; once you’re sure this has attracted his interest, the Mysis is released so it drifts down enticingly right before the seahorse’s snout. Most of the time, the seahorse will snatch it up as it drifts by or snap it up as soon as it hits the bottom (Giwojna, unpublished).

A great number of utensils work well for target feeding. I’ve seen hobbyists use everything from chopsticks to extra long tweezers and hemostats or forceps to homemade pipettes fashioned from a length of rigid plastic tubing. As for myself, I prefer handfeeding when I target feed a particular seahorse (Giwojna, unpublished).

But no doubt the all-time favorite implement for target feeding seahorses is the old-fashioned turkey baster. The old-fashioned ones with the glass barrels work best because the seahorses can see the Mysis inside the baster all the way as it moves down the barrel and out the tip. By exerting just the right amount of pressure on the bulb, great precision is possible when target feeding with a turkey baster. By squeezing and releasing the bulb ever so slightly, a skillful target feeder can keep a piece of Mysis dancing at the very tip of the baster indefinitely, and hold the tempting morsel right in front of the seahorse’s mouth as long as necessary. Or if the seahorse rejects the Mysis the first time it drifts by, a baster makes it easy to deftly suck up the shrimp from the bottom so it can be offered to the target again. In the same way, the baster makes it a simple matter to clean any remaining leftovers after a feeding session (Giwojna, unpublished). (You’ll quickly discover the feeding tube is also indispensable for tapping away pesky fish and invertebrates that threaten to steal the tempting tidbit before an indecisive seahorse can snatch it up.)

In short, target feeding allows the hobbyist to assure that each of his seahorses gets enough to eat without overfeeding or underfeeding the tank. And it makes it possible to keep seahorses in a community tank with more active fishes that would ordinarily out-compete them for food, since the aquarist can personally deliver each mouthful to the seahorses while keeping more aggressive specimens at bay (Giwojna, unpublished).

The key to keeping active specimens like firefish and occelaris clownfish or cleaner shrimp successfully with seahorses is to feed the other fish and inverts with standard, off-the-shelf aquarium foods first, and once they’ve had their fill, then target feed the seahorses (Giwojna, unpublished). <Close quote>

Okay, those are my thoughts on the matter, Nova. In your case, I don’t think adding a tang is the way to go. A 37-gallon aquarium is just not large enough to safely accommodate an active fish like a tang along with seahorses. The other tank mates you mentioned are excellent companions for seahorses providing you target feed the ponies and quarantine the fish first, but I would not recommend adding an expensive purple tang to a tank that small. Bear in mind that tangs are known as surgeonfish for a reason — they can do a lot of damage with their tail "scalpels" if they are so inclined — so you don’t want to crowd them together with seahorses in a small tank (remember how your schizoid yellow tang can go off on his tankmates unpredictably).

Tangs can also sometimes be problematic with seahorses because Hippocampus will often encourage algae to grow on its exoskeleton in order to enhance its natural camouflage, and the tang may then take to grazing on this algae to the consternation and harm of the seahorses.

All things considered, I would avoid adding a tang to your 37-gallon seahorse setup.

Best wishes with all your fishes, Nova!

Happy Trails!
Pete Giwojna

Dear Nova:

It sounds like you’re a very conscientious aquarist and that you already have a pretty good handle on things. That’s an excellent quarantine protocol you follow, and target feeding your gluttonous scooter blenny will be great practice for maintaining seahorses in a community tank.

Yes, sir — a dragonface pipefish would make a great substitute for the purple tang in the proposed lineup for your seahorse tank.

Best of luck with the seahorse community tank you are planning, sir!

Respectfully,
Pete Giwojna