Re:New Mated Pair doing great

Dear Ed:

It’s good to hear that your new mated pair of Sunbursts have settled in nicely and are doing well.

No, sir, female seahorses don’t normally eat less than the males or eat any less aggressively than the stallions do. As far as gender goes, seahorses in general, males and females alike, both have roughly the same caloric needs and eating habits. A breeding female does Devo a great deal of her bodily resources toward egg production, keeping her ovarian assembly line churning out clutches of eggs, but a pregnant male likewise invests a large portion of its bodily resources in nurturing a brood of developing young.

However, I have noticed that seahorses can sometimes be very selective when it comes to the size of the prey they prefer. Some seahorses are very particular in that regard, and tend to reject food items that are significantly larger or smaller than their preferred range of prey. For example, I’ve seen some seahorses that rejected the smaller Hikari Mysis with great disdain, yet which greedily gulped down the jumbo Piscine Energetics Mysis relicta. On the other hand, I’ve had small seahorses turn up their snouts at the jumbo PE frozen Mysis because it’s too large for their liking, and attack the small Hikari frozen Mysis with great gusto.

So if your finicky female is significantly smaller than the male, or if her tubular snout is too small to handle the larger pieces of Mysis readily, you might want to pick up a package of the much smaller Hikari frozen Mysis at your LFS for your filly instead. The Hikari Mysis is the smallest of them all and many pet stores carry the Hikari brand so it should be readily available.

And if she does better with the brine shrimp which are easier for her to swallow, then you can certainly continue to provide enriched brine shrimp for her as well. Just be sure to fortify the brine shrimp first in order to increase its nutritional value, and be careful to disinfect it before you offer it to your seahorses, as discussed below, Ed:

if you’ll be supplementing your seahorse’s diet with adult brine shrimp regularly, there are a few precautions you must be careful to observe. First and foremost, you must be careful to disinfect live food beforehand to assure you won’t be introducing any pathogens or parasites along with the prey items, as discussed below.

There is one potentially serious drawback to feeding your seahorses live brine shrimp on a regular basis. There is always the chance that you can introduce disease into your aquarium along the with the live food. Live Artemia (brine shrimp)are known disease vectors for a long laundry list of fish pathogens, and should be treated with caution in that regard – especially if obtained from your local fish store (LFS). The aquarist who relies on live foods for his seahorses MUST take special precautions to eliminate this potential danger!

Fortunately, there are a couple of simple measures that can minimize such risks. Decapsulating Artemia cysts, for instance, removes all known parasites and pathogens, effectively sterilizing brine shrimp eggs. Large public aquaria routinely go a step further, disinfecting live foods by administering a 10-minute freshwater bath and then rinsing it thoroughly through a 100-micron strainer before offering it to their seahorses (Bull and Mitchell 2002). Home hobbyists should do the same (a brine shrimp net will suffice for the strainer). Brine shrimp — the chief offender as a disease vector — tolerate this disinfection process extremely well. In addition, adult brine shrimp (Artemia sp.) are now available from High-Health facilities, which greatly minimizes the risk of disease contamination, and if possible, Ed, you should take full advantage of these safe vendors when purchasing live foods.

Secondly, you must be aware that unfed adult brine shrimp are virtually nutritionally barren, and it is therefore vital that they be enriched improperly before you offer them to your seahorses. It is a great idea to enrich the brine shrimp with Vibrance, but make sure you use the lipid-rich Vibrance I rather than the low-fat formula (Vibrance II) for the Artemia. Adult brine shrimp are a good source of protein, but they have very little fat content. The lipid-rich formulation in Vibrance 1 (the original Vibrance) is thus ideal for enriching brine shrimp, transforming them from nutritionally barren, empty calories into a high-fat powerhouse of vitamins and nutrients that’s loaded with color-enhancing carotenoids. As an added benefit, enriching brine shrimp with Vibrance is also an excellent way to get your seahorses to ingest beta-glucan, which will boost their immune systems and help keep them healthy.

Fortunately, brine shrimp are filter feeders and will take in whatever is suspended in the water with them that has a manageable particle size, including Vibrance I. This can be Vibrance, yeast cells; unicellular algae; rotifers; micronized rice bran, whey, wheat flour, or egg yolk; dried Spirulina algae; water-soluble vitamin and mineral formulations designed for marine fish; or whatever else the aquarist cares to add to their culture water (Daleco Aquarists Supply Manual, 1995).

I recommend using one of the concentrated food additives or enrichment products that have recently been developed specifically for mariculturists. The best additives are rich in lipids, especially highly unsaturated fatty acids (HUFA), and vitamins such as stabilized Vitamin C and cyanocobalmin (B-12), such as Vibrance 1. Adding such enrichment products to a 6-ounce portion of brine shrimp, and then allowing a short period for the shrimp to ingest it can fortify store-bought adult Artemia (Giwojna, Oct. 1996)

Liquid vitamin formulations can also be added, and the ability to enrich their lipid and vitamin content this way allows us to treat brine shrimp as animated vitamin pills for seahorses (Lawrence, 1998). The savvy seahorse keeper should regard enriched Artemia as bio-encapsulated food for his charges and take full advantage of every opportunity to fortify the shrimp (Lawrence, 1998).

Although he feeding behavior and nutritional requirements of male and female seahorses are similar, there is a great deal of very ancient in the eating habits of seahorses from individual to individual. 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 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).

So it’s certainly possible that your female Sunburst is just naturally a slower eater than the male, Ed. If that’s the case, you may have better results if you target feed her using the smaller Hikari brand of frozen Mysis. Or you can continue to offer her enriched brine shrimp, which she is able to eat with no difficulty.

However, sometimes feeding difficulties such as you describe are due to an affliction that is commonly known as weak snick. It results when seahorses has difficulty generating strong suction when they are slurping up their food, especially the biggest, heaviest food items. So keep a close eye on your female to determine whether she is simply a slow eater or is having trouble generating enough suction to eat properly, which could be a symptom of a more serious problem.

Best of luck with your new seahorses, Ed! Here’s hoping that your female is soon able to handle even the largest pieces of Mysis with ease.

Respectfully,
Pete Giwojna