RE: “If it’s yellow
Let it mellow
What the heck does “let it mellow” mean? How yellow should it be before we flush it?
Your decision. You're using a gallon of water each time, so when you flush after every use, it starts to add up. This is especially so when you're in desert country or anywhere you pump your own water. In rainy areas I wouldn't worry about it.
Out here in Arizona, even though we're on a regular system, the "yellow" gets pretty bright - until the wife finds out. ;-)