adding a UGF to a set up tank........

I recently got a used Powerhead 802 in a group of supplies and wanted to set it up to somehow help filter one of my tanks. Idealy I wanted to use it to power a UGF in my 55 gallon but being fully stocked I decided to wait instead of disrupting all my tetras and stressing them out. I found a filter made to screw onto the powerhead and thought it might work on my 36 gallon 1/4 cylinder that has pretty fastmoving fish anyway. I have 11 barbs, 3 giant danio's and 2 green banded danio's along with a gold gourami. I figured they'd like the fast moving water anyway. I set it up and quickly figured out I'd have to move my plants all to one side. That done, I cranked it down to it's lowest setting and at first it was amusing. The danio's loved it and the tiger barbs thought it was pretty cool and would venture into the current. One barb shot across the tank and smacked the glass and went back for more. After an hour or so they got tired of it and retired to the planted section so I opted to remove it and let them have their peace. I could just keep it on the shelf waiting till I get a bigger tank to actually use it on but I just can't stand having such a cool gadget sitting there going to waste. Has anyone ever installed a UGF after the tank was set up and stocked? How'd you do it? would you do it again? I'm assuming a 55 gallon UGF would have two inlet/outlets. Would I be better having this on one end, in the middle somewhere or do I need to have two smaller powerheads? thanks, Kyle

hmmm. I liked the idea of forcing water up through the substrate since my tank has lots of plants and decorations and is hard to vacuum. thanks, KYLe