WandaLust2 wrote:
I personally wouldn't want funky greasy soapy gray water sitting my toilet bowl between flushes. We only have two waste tanks so can't draw bath water which can also get smelly what with soaps, hair, body oils and skin cells decomposing in it. No thanks. What a mess that would make the bowl to clean each day and gross to see and smell every time the toilet was used.
Forget the toilet bowl, what about the toilet itself or the spray nozzle. If one adds a bypass on the toilet's water line to use gray water then one has water with substances suspended in it that may very well settle out and coat the water channels under the rim of the toilet and/or the spray's water hose and nozzle. Reminds me of cholesterol plaque building up over time in one's arteries. One could end up servicing or replacing the toilet and/or spray in the future.
Now if one is using a separate spray that is served only by the gray water then one only has to deal with the second spray when it gets gunked up over time. Shut off the water to the toilet, turn on the gray water to the gray spray and service the gray spray when it gets clogged.