Beadlet Anemone

Dear Judy:

Unfortunately, the beadlet anemone (Actinia equina) is not safe for seahorses. Like all anemones, Actinia equina is equipped with stinging nematocysts that can injure seahorses. It would be unusual for Beadlet Anemones to enter a tropical aquarium as a hitchhiker on live rock, Judy. It is very common for anemones to hitch hike on live rock, but they are almost always Aiptasia anemones rather than Actinia species, so I’m thinking that you may actually be dealing with an outbreak of Aiptasia rock anemones.

A few isolated Aiptasia rock anemones won’t pose a serious threat to any of the larger seahorses such as Mustangs and Sunbursts (Hippocampus erectus). In most cases, the seahorses be careful to avoid them.

However, Aiptasia rock anemones can rapidly increase in number and become a threat to seahorses when they are so numerous it is difficult for the seahorses to avoid coming in contact with them. The danger is not that the Aiptasia will capture and consume a small seahorse, but rather that their stinging cells or nematocysts can penetrate the integument of the seahorse and leave it vulnerable to secondary infections. So the bad news is that I would strongly suggest that you take measures to eliminate the rock anemones before their numbers increase any further. The good news is that user they shouldn’t have to strip down your tank in order to get rid of the, Judy.

Aiptasia rock anemones can easily be killed by injecting them with a number of solutions — Kalkwasser, boiling water, lemon juice, a number of commercial products such as Joe’s Juice — and I suggest using a combination of such injections and biological control to eradicate them.

Peppermint Shrimp (Lysmata wurdemanni) will do a fine job of controlling Aiptasia rock anemones and they do great with seahorses. 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.

One rule to keep in mind when buying your Peppermints is to select the largest possible cleaner shrimp for your seahorse tank(s). Seahorses will actively hunt small cleaner shrimp and they are quite capable of killing shrimp that are far too big to swallow whole, so the cleaners need to be large enough that they are not regarded as potential prey. Add a few good-sized peppermint shrimp to the seahorse enclosure and they will happily clean up all of the smaller Aiptasia rock anemones.

If you pitch in by periodically injecting the largest Aiptasia, you will soon whittle down that forest of rock anemones. As the number of Aiptasia are reduced, they will become easier and easier to eliminate. There will be fewer of the large anemones for you to inject and the peppermint shrimp will eventually work their way through all of the smaller ones.

I must also warn you that attacking the Aiptasia rock anemones with sharp, pointed instruments or the like will not be enough to kill them. Aiptasia anemones can reproduce by budding and by fragmentation of their pedal disc or foot. So it isn’t enough to destroy the head (oral disc) of the anemone, you must eliminate the entire foot or it will simply regrow from the pedal disc and even spread if the pedal disc was fragmented during such assaults. In other words, it’s always better to try injecting them rather than skewering them or attempting to physically destroy these pesky little anemones.

Best of luck eliminating the Aiptasia rock anemones before they get out of hand, Judy! (Would you be interested in participating in Ocean Rider’s free training course of the carrot keeping of seahorses, Judy? What the tighter messages devoted to a discussion of the compatible and incompatible tank mates for seahorses.)

Respectfully,
Pete Giwojna, Ocean Rider Tech Support

Hi Pete – Forgot to mention that the guy who we bought the rock off used to ‘breed’ and sell beadlets so thats where they probably originated from – what does joining that training club entail – thanks Judy