[BB_TX]

I use nearly 4 gallons. But I don't attempt to minimize usage. I let it run thru each faucet until it runs good and pink and puts antifreeze in the P traps. And the clothes washer hot and cold lines take quite a bit plus making sure I get it in the washer drain P trap. And then there is the toilet, and the black tank flush line, and the outside shower lines. No more than it cost I don't worry about using too much.

I use the propylene glycol antifreeze rather than the cheaper ethanol based antifreeze.