The shrimp Thor amboinesis is a symbiont shrimp, that in nature live on different species of anemones, so more the home aquarium is similar to the natural habitat, more success could be reached in the breeding of this small crustacean.

Whether the tank is populated by other fishes and crustaceans, it is essential to maintain Thor in pair or better in group and, above all, they need a host anemone, otherwise they could be preyed by bigger fishes and crabs. Personally, I breed them in pair, commensally with the anemone Stychodactyla tapetum, but they could well settle also on cerianthids, LPS- and soft corals.

The feeding protocol of adults is very easy, because these shrimps eat immediately frozen foods and pellets, but it’s important to feed them regularly, otherwise they will destroy coral polyps, such as zoanthids, xenia and other corals.

 pair

As of the reproduction, Thor amboinensis are protandric hermaphrodites, so young individuals are males and the oldest and dominants in the group become females, so it’s easy to pair some young shrimps because in few weeks, a female will appear as the bigger among the group.

Once hierarchies are established, spawning become a routine, since larvae hatch every 14 days. Also the hatching time is precisely regulated, meaning that larvae are released one hour after lights are turned off. Thus, when female is ready, she climbs a rock or a coral and she waits for a quiet moment to release larvae.

Larvae have positive phototactic response, so they could be simply harvested with a pipe or with a trap, after grouping them under a light cone. The larvae so harvested, now must be placed in a small container, linked to an air pump in order to keep them floating in the water column, because of their planktonic nature. Personally, I use a tall cylinder with a small base surface.

 1 day old larva

Furthermore, the feeding protocol of this kind of larval shrimps is quite easy, in fact larvae can eat immediately brine shrimp naupli, but they can also be maintained in green water technique with rotifers. The procedure of water changing and cleaning must be granted every one or two days, in order to preserve an high water quality and in order to replace old naupli with new nourishing live food.

At this point, well kept larvae will pass through different moltings: the first one occurs after three days, while the last one happens along the fifth week post hatch, depending on temperature and water and food quality. The last metamorphosis corresponds to the settlement on the bottom, so when the first juvenile Thor appears, we must provide new sources of food, like freeze-dried dusts and small pellets.

 25 days old larva

I suggest to maintain young Thor amboinensis in the same container, until they reach real adult coloration, that is about eighth week after hatching, then they could be introduced to adult life in the reef tank with their hosting anemone.

 young shrimp