to the forums. If you kept the jugs the antifreeze came it you can recover some of it by opening the low point drains. Otherwise hook up a hose and start rinsing it out. I haven't used antifreeze in quite a while but when rinsing I usually opened my grey tank drain and just allowed it to run out. It becomes so diluted it doesn't harm any thing. Don't forget to change the position of the water heater by-pass once you've completed your rinsing.