I collected 3 small cushion stars about 6 months ago (ended up having 4, not sure where the other one came from). They are thriving in my tank and are now large (about 1.5cm across) and thick with stunning colors. I am however baffled by the lack of information on then online in terms of keeping them in a reef tank? The only reference I could really find on them has been in the Two Ocean guide . From the guide I deduced that the once I have is Patiriella exigua and not P. dyscrita based on having collected them from rockpools. How would one make a positive identification? My ones also looks like they filter feed as there is "polyps" on their top side (see pic) and they often like sitting in high flow areas. According to the book they are algae film feeders (only)? Does anyone else keep them and have more information on them? If it is P. exigua, they are egglayers without an plantonic stage, it would be interesting to see if they can reproduce in a reef tank. Has anyone had success with them?