can anyone please confirm one way or another if this is a sponge, I think it is and was wondering if its a cryptic sponge, if its not does anyone know what type it is and wheather or not i should get rid of it
Thats what I'm thinking, I've looked at a few photos of sponges and a cryptic sponge comes the closest, its just that you can read so many different opinions and half will say they're good and the other will say they're bad, but a cryptic sponge seems to be one of the few good ones
It certainly looks like a white encrusting sponge to me. Very common, beneficial filter feeder. You will also end up with blue, green, black, yellow, red, and pink varieties if your system is going long enough. if it seems as if some are going to overgrow a coral you can easily scrape them off, but do it in a separate bowl of water - the individual pieces that float off can easily become whole new colonies.