I recently dove for the first time in a 5 mm wetsuit. I added weight to compensate, 4's in the BC pockets and 3's in the tank pockets (I use 3's and 2's with my 3 mm). My problem is that I have done 3 dives in the suit and still want to do a face plant and my feet float to the surface. I normally have slightly floaty feet but in the 5 mm if I stop swimming I almost immediately start to go head down and feet up. It was so bad the first time that my knees ached for hours after from fighting to keep my feet down. I tried lowering the tank and it helped some but if I go any lower, the tank will be on the ground! (I'm 5'4"). It's bad enough that I decided I'd rather be cold in my 3 mm and have switched back. I hate the idea of ankle weights. Any suggestions? Thanks for your help.