this has worked for me very well for my 50 gal. will be making A MONSTER one for my 180 Gal. i used 1/4" air line tubing 4" dia. x 4' long pvc. took 4-6 weeks for 0 ppm to come out and 8 weeks or so for my tank to be at 0 ppm from 15 ppm. havent changed my water for 3 months now. it not ez to make, thats why im making a couple for other people. if you want one made, let me know. have fun and good luck.
