We are going to be putting black and grey tanks in a 1950
liner. I am wondering if both tanks could use the same vent through the ceiling. Both tanks will be close together so tying them wouldn't be an issue. This would eliminate a second hole in the roof. Only issue I can think of is if both tanks are draining at the same time, it might not allow enough air into both tanks for air displacement. We usually drain black, close black, then drain grey so may not be an issue there but wanted to hear if anyone has done this or if a plumbing expert on here might know of another reason this might not be a good idea.