tough call...

I've ran my 280 in 10" of water since day one, added a higher baffle to my sump wich put it in 11" of water and I like it better now!!

But... you'r better off figuring it out now prior to silicon hitting the baffles..so my opinion doesn't really help the dilema!!!lol

I already cut out the baffle so I should probably shorten it while I can.
15"of water should be fine I think.