Okay this is what I know. All nudibranch are hard to take care of and like Greatfullreefer said they should be left alone. But there is one exception. The Lettuce Nudibranch. Well it is actually a Sea Slug more than a nudibranch (but your husband doesn't need to know that). It east algae and also gets food from phyotosenthisis like plants do. But they are very delicate. You must screen off all you intakes to filters, powerheads, etc. or else they will hurt themselves and brobably die. I have never seen them listed as toxic before but the other nudibranch... well just stay away from them even know they are very pretty. :yes: