I'll let you know in about a month. That's how long I was told it would take to see a difference with the 2 Berghia Nudibranchs I just got. They will spawn and their numbers will flourish until they run out of food, in which they will then die. My LFS told me they will have no problem eating the smaller aiptasia, but might have difficulty with the larger ones...and I got some juicy fat ones. So I was told to continue using Kalk paste on the big ones and let the nudis handle the smaller ones. But to be honest, ever since I've put them in, I have yet to see them again...and that's in a 10 gallon sump/fuge