I was thinking a quart a flush.

OK, I have to work a different tank in there somehow.

Actually we do "extend it a bit" by following the old California water saving trick of "if it's brown, flush it down, if it's yellow, it's mellow." We "collect" a bit, then flush.

Thanks

BTW the fresh water flush system* really has eliminated all odors. *using fresh water from the lav to flush, vice sea water.