I'm sure they are.

Went downstairs to check on the new guests. Suckers seemed to be snoozing in the corners. Shined my flashlight on one. It looked at me with kinda that look like GO Away! It's dark down there.

I have another BW 350 cycled if need be.

One thing I was thinking is get some 3" PVC pipe with a 3" dia airstone under it. Drill a bunch of holes in it and toss some of the media in there. Stand it upright in the tank. Should work OK and be easy to clean when need be.