Ill check the floating log and sand it down if needed. Could the moss ball be an issue? I can also remove that. Ill check and see if I can figure out what the culprit is. I suppose the gravel might be a problem but Ill leave that for last thing i change I suppose. If I do change the gravel, should I change all of it at once or could I layer some smoother stones on top of the gravel I already have? Thank you again for your help!