Gray water tank flows into black?

[MNFamilyCamper]

We're still in our pop-up camper so no holding tanks currently and it's been a long time since high-school and managing the gray and black water dumping in the family camper...

Is it typical for the gray water holding tank to "overflow" into the black water holding tank once it gets full? Or is each holding tank entirely isolated (except for the drain pipes)?

[w4drr]

They are totally isolated. You don't want to be cross-pollinating those holding tanks.

Bob

[HONDAMAN174]

Both tanks are kept seperate. Usually, grey water tank will "back up" into shower or sink when full.

[MNFamilyCamper]

Thanks for confirming. I certainly understand the potential for cross contamination and keeping things clean.

Given what I expect to be the ratio of water usage (much more gray than black), I'm surprised that the Rockwood UltraLites we're looking at all tend to have roughly equal black and gray water holding tanks (37 gal).

[RoadTrip]

Originally Posted by MNFamilyCamper

Thanks for confirming. I certainly understand the potential for cross contamination and keeping things clean.

Given what I expect to be the ratio of water usage (much more gray than black), I'm surprised that the Rockwood UltraLites we're looking at all tend to have roughly equal black and gray water holding tanks (37 gal).

I hear ya. 50 gallons of poo just seems excessive...

I believe bclemmons once opined that the sizing has more to do with what will fit in that designated space. So even though you don't *need* 50 gallons of black tank space - it was either that or a smaller size, but still no room for anything else.