We had TC with a 25 gal black tank.
Family of 4, “most” #2s deposited in the camper toilet. Less than 50% of #1s in the camper. 1 week was about the practical limit. More than a week and you didn’t want to drive very far before dumping it!
2 people, 25 gal would comfortably go a week I’d say.
The recommendation to use plenty of water with flushes is valid, to a point. If parked long term it’s more critical. If camper is mobile, shaking things up does a good job without alot of “extra” water.
IMO, for boondocking fresh water capacity is the biggest priority by far. Black tank second, grey water 3rd. Bigger the better obviously. But despite some of the comments about how horrific it is to dump gray water in the woods, it can really be done very easily and cleanly and without scrutiny from those around with just a little common sense.
I know the replies will start flying over my last comment so let er rip, but if you were camped next to me you wouldn’t know I just dumped my gray water last night, so ya wouldn’t have anything to complain aboot! Lol
