My clowns were digging when I had my 55 setup, bugging the crap out of me, when I got a BTA I put it about 10 inches off the sand, the clowns found it within a few minutes (gold striped maroons) and no more digging . The clowns didn't dig after they were transfered into the 92g, the rose BTA they are currently hosting in is about 15 inches off the sand. So long story short, I haven't had a problem with my clowns digging since I got them an anemone and placed it up high...