Re:sexy shrimp

Dear arcprolife:

Sexy shrimp (Thor amboinensis) are colorful and their dancing is entertaining to watch. They are peaceful and get along together in groups or colonies. They are seahorse safe but I would fear for their safety in an aquarium with large seahorses such as Mustangs or Sunbursts (Hippocampus erectus). As you said, they are pretty small for shrimp — most specimens I have seen range from about 1/4 to 1/2 inch in length — and that makes them fair game for hungry seahorses.

Remember, live shrimp are the favorite food of all seahorses and, up to a certain point, they will not hesitate to attack shrimp that are too large to be eaten in one bite.

This often happens when feeding seahorses live ghost shrimp or grass shrimp, many of which are too big to be eaten intact. Seahorses are so fond of these shrimp that they often attack specimens that are far too big to swallow. In that case, they will attempt to break the back of the shrimp by snapping repeatedly at the carapace. If they are successful in severing the abdomen from the cephalothorax, the seahorses will then slurp up the tail section and head half of the shrimp separately. Or should their victim be so large it cannot even be swallowed in sections, they will snick out mouthfuls of the soft tissue exposed inside the abdomen or thorax.

At times, several seahorses will gang up on one big shrimp this way, like a pack of lions teaming up to bring down a water buffalo that’s too big for any one of them to tackle alone. Under the right circumstances, a sort of slow-motion feeding frenzy may then ensue, with the seahorses playing tug-of-war over the pieces of their prize.

Grass shrimp that are too large to be overcome by such tactics may survive to become long-term residents of the seahorse tank, coexisting with their reluctant tankmates in a sort of uneasy truce. Such die-hard shrimp provide a useful service as scavengers from then on.

In short, I would be concerned that large seahorses would regard your sexy shrimp as tasty snacks. If your barbs (H. barbouri) are fully grown adults, you might be better off selecting one of the decorative Lysmata shrimp species instead. For example, Peppermint Shrimp (Lysmata wurdemanni) and/or Scarlet Cleaner Shrimp or Skunk Cleaner Shrimp (Lysmata amboinensis) and/or gaudy Fire Shrimp (Lysmata debelius) would complement your cleanup crew and add a touch of color and activity to your seahorse tank.

I have never tried keeping sexy shrimp with dwarf seahorses and that might be an interesting experiment, arcprolife. But even if they coexist with the adult H. zosterae without any difficulties, I wouldn’t trust them with the newborns. Many times shrimp are active after lights out when the seahorses are at rest, and these pint-size pigmy ponies would be vulnerable at this time, especially any of the young that are in your dwarf tank. I don’t think I would risk it, sir.

The only shrimp I do trust with dwarf seahorses and their babies are the Volcano shrimp or Hawaiian red feeder shrimp (Halocaridina rubra). These colorful little saltwater shrimp resemble miniature peppermint shrimp, and usually do well with dwarves because of their size. They are too big to be eaten by the seahorses and too small to be any threat to them or their young, and as an added bonus, they will produce larval shrimp that are perfect treats for the ponies. They are omnivores that do a fair job of scavenging and complement the regular clean-up crew nicely (Giwojna, 2005).

Along with the Volcano shrimp, Nassarius snails and Scarlet Reef hermit crabs (Paguristes cadenati) can serve as the cornerstones of the clean-up crew for dwarf seahorse tanks. The Scarlet Reef micro-hermits are colorful and interesting in their own right, and these harmless herbivores are the only hermit crabs I trust with my dwarf seahorses. A few of the colorful Scarlet Reef crabs make nice additions for a dwarf seahorse tank, as do the Nassarius snails, which are very active, efficient scavengers that handle the meatier leftovers.

In short, arcprolife, I don’t think the sexy shrimp are your best choice for a seahorse setup. The shrimp themselves would be at risk from the larger seahorse species, whereas the sexy shrimp could pose a danger to sleeping dwarfs and their young.

On the other hand, both the H. kuda and H. reidi should make good tankmates for your barbs (H. barbouri). Those are all tropical seahorses with virtually identical feeding and aquarium requirements. They should all get along very well together, but it would be best if you can obtain all of your seahorses from the same breeder.

Best wishes with all your fishes, arcprolife!

Happy Trails!
Pete Giwojna