The first picture is a nudi the second picture is a colony of hydroids.
The nudi could be bad for Z's and P's but hydroids can be bad for many things. They sting and that will have bad affects on a lot of coral, and one other thing you nee to know about Hydroids the sting can paralyze a seahorse and even kill young ones. So you need to do something, ether do something to get rid of the hydroids or move the seahorses.


Quote Originally Posted by cg5071 View Post
Will do. I did find a nudi yesterday though too. I got a pic and will add that before linking it over at Bobs. I kept it in a cup overnight hoping it might be a berghia lol. It was dead today though. I also found a massive colony of the other things on a normally hidden part of a frag shelf.