[rohrmann]

Beware leaving the tanks that full too often, especially with the ABS tanks. I had to repair a crack in the bottom of our grey tank last year where the flexing of the bottom of the tank ultimately caused a crack in one of the molded ribs. I was able to fix it with a Plastimend kit. I added a couple extra braces across the frame below the tanks, and installed blocking between the braces and the bottom of the tanks. They don't flex now and I don't worry about ocassionally having water back up into the shower. This also keeps the same thing from happening with our black tank.