Although the common name for them is Orange Ball Anemones, the Pseudocorynactis are not anemones at all. They are a type of corallimorph, or, in other words, mushrooms.
Mushroom corallimorphs come in a variety of shapes, sizes, and textures, but even within a group with this kind of diversity, the Pseudocorynactis is an oddball character. It is easy to see why one might think of it as a type of anemone. They share some similarities with some of the popular true anemones in the hobby: they have a thick tentacle crown, long tentacles with bubble tips, a fleshy body, and a single large mouth in the center.
There are a number of species, but the most familiar is the Caribbean Orange Ball Corallimorph, Pseudocorynactis caribbeorum.
Appearance isn’t the only thing Pseudocorynactis has to distinguish itself from the mushroom crowd. It is easily the most effective predator (with all due respect to the Elephant Ear Rhodactis that has eaten plenty of fish). The lovely tentacles of the Pseudocorynactis are incredibly sticky. Their stickiness is on par with the a large carpet anemone. Once it gets its nematocysts locked on its target, it doesn’t let go. It is possible to lift the entire Pseudocorynactis out of the water, held only by the stinging barbs embedded in your skin, if it grabs your hand.
This “stickiness” and ability to respond quickly to animals that unfortunately come in contact with it make the Pseudocorynactis a poor choice to house with many small fish or invertebrates. They are really good at catching and eating anything that wanders too close.
At Tidal Gardens, I like to keep them in a refugium of sorts with just macroalgae. They can’t do much damage to macroalgae. In a tank like this, I can still appreciate them for what they are in a nice setting, but don’t have to worry about them eating something like a Foxface or a Purple Tang. They are more than capable of grabbing and eating large prey items of that size. The largest one we’ve ever grown was a good 12” across and could eat a Naso Tang.
In summary, the Pseudocorynactis can make a really interesting oddball addition if you are willing to take some precautions to account for its aggressiveness. They are hardy, stay in one location, and can be propagated easily. Check out the video to see it in action!