wierd slugs in my zoos. HELP

[Dale]

I've dealt with those nudibranchs several times also and have had success with repeated FW dips. In my case I am much more aggressive than previously suggested. I take the rock/colony and hold it under the tap for about a minute, letting the water jets shoot in between the polyps to blow everything out. Strong medicine to be sure but several repeats of this does eliminate the nudi's.