recently I've noticed some odd fish behavior in my aquarium with my lawn mower blenny and bristletooth tang. my blenny has found a nice spot off at the end of the tank and has started to dig in the sand and hollow out a hole. i thought he was just "claiming" that spot for his own. as i was watching him do this with interest, my tang came over a pooped on him. i chuckled and thought that was funny. well like clock work 5 minutes later he did it again. as i watched for about 20 mins, he consistently did this every 5 or 6 minutes. i caught them on my cell video camera. why do you suppose this is happening? i find it very odd behavior indeed.