I have recently installed a whole house water filter, water softener, chlorinator and sediment filter. This was all easy plumbing with 1" PVC. My problem is that the filter has a Fleck valve with a 1/2" ID flexible plastic pipe that is used to recycle the filter. It backwashes overnight a few nights a week to recycle the filter. My problem is how to correctly install this line to my house drain line with the proper air venting that needs to be done. My main drain line is roughly 3" PVC (haven't actually read the measurement off the pipe). Currently I'm just running this drain line outside the house, but I'd really like to run it into the drain line and to my septic system so that all this water that is being pumped onto the ground doesn't become a huge mud puddle. Thanks!