I have 2 dwarf puffers that I usually give frozen blood worms to. I usually let them thaw, then put them in the tank. The stuff kinda goes down to the bottom of the tank where they puffers stalk & eat it. Last week, though, was the last week of school so I was really really busy & usually didn't have time to thaw it, so would just throw it in (it floats then). Now I find that when I thaw the cubes & throw them in, the puffers attack it while it goes down, then leave it alone when it sits on the bottom. I was just curious as to whether your puffers eat at the top or bottom of the tank?