i have a mottled sculpin in my 10 gallon tank with guppies..hes about 2 inches and has recently found out how to shove a hole male guppy in to his gut, witch i did not think possible, but no dead body and a very full Sculpin was all the proof i needed,
i wouldn't recommend them unless you dont have anything that you think might fit in to his mouth, or anything smaller then it seems, hes only about 2 inches now can get to 6''...
he ate the guppy even after a big meal of bloodworms the day before
..love sculpins but maybe not for a community tank , unless you don't mind restocking what it eats