My lawnmower blenny has grown alot since I picked him up a few months ago and he has stayed for the most part in his little cave. He loves algae of course, but he also eats pellets that float his way with vigor! This week I added a small (very skinny) Mandarin goby and now the blenny can be seen all over the tank! I have lots of little bugs for the Mandarin and I'm hoping he plumps up, but its interesting to see an algae eater seem to be concerned about this addition. They don't bother each other at least.