While I have you on the hook (pun intended)
one of the pet smart people told me that guppies were "turbulent sensitive". I have an under gravel filter, and a fluval U2 filter and an airstone under a rock. My tank IS pretty turbulent. My fish seem happier with all the current...but what do I know?
What do YOU think? I like the bubbles, the kids like the air bubbles, and I swear the fish do, too. Even the snails crawl over the bubbling rock and get caught in the upstream, and then turn around and do it again. I dont know how smart a snail is, but....The fish seemed to get better AFTER I installed the FluVal filter. Am I hurting my fish? All the sick problems came BEFORE the turbulence.