Anti Freeze in Black Tank

If winter camping try using a saltwater solution, saltwater freezes at a lower temp than regular water and is a lot cheaper. if your just winterizing I would just dump them rinse real good and cover the bottom with anti freeze but you really don't need any at all

The strength of RV antifreeze and windshield washer antifreeze become very weak when mixed with anything at any quantity, that is why they should be used full strength. The only thing that may happen is the fluid will crystalize instead of freezing to a solid block. This is still better than busting your tanks but the best solution is as Oasisbob says” Just dump your tanks before you go to bed”

Oasisbob wrote:
Just dump the tank before you go to bed. If a gallon of water is on the bottom of the black tank and freezes I cannot imagine how that wold expand and damage tank. Am I ignorant on this? I have been before. What say all of you?

Ditto. Same goes for the fresh water if there is a minuscule amount in that tank too.

Someone mentioned windshield washer fluid... I used this for the flushing medium in my cassette tank.

Just dump the tank before you go to bed. If a gallon of water is on the bottom of the black tank and freezes I cannot imagine how that wold expand and damage tank. Am I ignorant on this? I have been before. What say all of you?

i use the cheaper blue windshield washer fluid. good down to -20

Assume you are planning cold weather camping. When camping in my precious TT with enclosed tanks I would winterize helow 10 degrees. I used bottled water for drinking, cooking and washing. I flush my toilet using anti freeze. Actually I have found that the black tank actually stays warm because of composting and breaking down of solids. In the grey tank I added anti freeze as I added water and seemed to work out OK.

tuna fisher wrote:
If I was to put RV anti freeze in my black tank how would that work? My black tank is only 12 gal. how much would I need if it was to be near full without making it to weak.

Probably 12 gallons. It's supposed to be used full strength. Car anti-freeze would be better.. but then you have to get rid of it.

If you have time you can always run your own test in your freezer at home.

Does your tank already gave waste in it?

If not I only put about a 1/2 gal, you don't need to fill it