Shadow, I use the same winterizing kit and it works very well. 1 gallon is barely enough. I usually use that plus a bit more. But that doesn't really go to waste for me because I usually winterize before heading north and if I need to use the toilet I just add more pink stuff/use it to rinse. Obviously I empty the tanks again and add more pink stuff when I store it. #Jt646, if you put the winterizing kit where Shadow explained, between the fresh water tank and the pump, then the pump either draws from the fresh water tank OR the line that is put in the pink stuff. so the antifreeze never touches the fresh water tank, only all the lines and the waste tanks. You can do it all from inside, so you can set it all up with the switch to the antifreeze bottle and the line in the bottle, then make sure your hot water bypass is in place, be sure to empty the hot water tank before hand. Then when all that is done, just turn on the pump and open the faucets one by one until you see pink stuff run out, turn it off and open the next faucet and so on, to include flushing the toilet and running the shower. And any outside shower if you have it.