Combining the Black and grey tanks after installing a composting toilet

[Chrisy]

Is it possible to combine the Gray and Blackwater tanks?

[andreasduess]

Yes and it's easy. All you need is an extra valve that you put on the end of the waste pipe. Then, open both the old black and the old grey valve and you're done. The water will auto-level amongst the two tanks. Check how the Wynns do it: http://www.gonewiththewynns.com/comb...lack-grey-tank