Manny,

Your toadstool does eat, but only really small stuff like bacteria and absorbs organic nutrients from the water. I have heard of people stirring their live sand to put more bacteria in the the bacteria for them. They are mainly photosynthetic.

You hairy mushrooms (Rhodactis) like meaty stuff like brine shrimp but I don't think it is entirely necessary. I just like watching them feed. To the best of my knowledge the bullseye's (Discosome) don't feed much but mainly absorb nutrients and really small stuff.

Your colt definitely needs to be fed. It'll do well with DT's. Sometimes if you have critters such as snails or Tangs that are feeding on algaes in your tank they will stir up enough to feed the colt.

I think the feather duster feeds on just about everything but particularly on algae's such as DT's.

Hope this has been helpful,
Gary