WHat about a tube anemone. They do not require light, in fact they can be damaged by really good lighting. They are very colorful but are masters at getting into intakes so make sure all are protected before you get the anemone. They are filter feeders and really open up well in a tank with alot of flow. Here the orange ones and the purples are pretty easy to get and after seeing them first hand, they are some of my favorites.
As far as looking for an anemone for your clowns to host, it would be hit or miss, some will and some won't even with an anemone that they are "supposed" to host.
You may want to keep in mind that there are alot of kids and newbies here on the forum that just want to help. I am sure that Zeke was only trying to offer a little insight. I would much rather see someone come forward and tell you that they are not an expert than someone who represents themself as one, which does happen quite a bit.