I have a medium sized purple tang in the 120. he is happy happy what the heck no issues. I am wondering if I could get by with adding a small PBT in there as well. I have 2 vortechs running at 3/4 in reef crest mode, so there's tons of flow in the tank. I was thinking of printing out a few PBT pictures, and taping them to one side then moving them every day or so.... any idea if this will work?