I was wondering if anyone had a recommendation on slowing or blocking the filter flow in a tank. I am planning on purchasing dwarf puffers, who prefer less water flow. Actually all fish would probably appreciate a less forceful current than what my tank has now. I have the 12 gallon nano cube tank. There is not a way to really turn down the gph, nor would I want to. However the output is very fast. So how should I slow it down? I plan on adding rock stacks in the tank to aid in hiding and such, this might help if I form it around the output flow? I would encircle it but leave plenty of space so that the water would continue to move outside of the ring. Or perhaps they make an actually object for this purpose Thanks in advance!