Anti Freeze in Black Tank

tuna fisher wrote:
I guess I have to explain myself. I'm looking at the future camping. My tanks aren't enclosed, I plan on using bottled water and not using my gray water tank but a wash tub. Just using the black tank for what it's meant for. Dumping at night is out of the question as I'll be boon docking. Flushing with anti freeze sounds doable. I guess the ? is how strong of a mix poo vrs anti freeze.

What I did in your situation before my current camper with cassette would be to literally use undiluted windshield washer fluid (yes, because it is cheaper than RVAF) as the flushing fluid. Since the domestic fresh water would be winterized, I still used the toilet and pour from the jug the WW fluid to wash down the poop.

The black tank would be poo and WW fluid and it did not freeze even down to 0 and colder. It worked for me. When emptying the black tank it did not need a drain hose because my particular camper had the black valve outlet directly vertical in the down direction. I have a lift station with manhole in my drive way so all i had to do is line up the outlet over it and pull the valve open. There could be some issues using a flex hose when dumping in really cold weather if folks need a hose to dump. This is why I like my cassette for winter camping: self contained and easy to dump in cold weather.

I don't have any direct experience yet but have given it some thought . My tanks are enclosed and with some fans can get some heat to them . The concern that I have is the cap which s exposed . I plan on putting some pink stuff in the empty tank to start and opening the valve for a second to let it fill the cap area . I have a cap with a hose connection to relieve it before emptying the tank . May have a chance to try this over the weekend .

I sometimes camp in below freezing weather and here's what I do. My camper and many others (I think) have diverter valves for easy winterization. You throw the valve and then just take the short piece of hose which is directly connected to the pump and stick it in a bottle of the pink stuff and run the various faucets until they run pink.

When finished winterizing, I leave the hose set up with a full bottle of pink stuff (jamming the bottle so it doesn't move around). Then when I flush, I'm flushing with the pink stuff. All other water usage is from bottled water. Your mileage may vary but on at least one occasion I booondocked for two nights with dead batteries (so no heater) with temperatures of -1F and 0F at dawn. No problem observed and was able to dump without problems when I returned home (warmer temps but still around freezing).

dks wrote:
Why do people use windshield washer fluid (that is toxic) when there is a product already made that is not toxic? Surely the $2 difference is a small cost.

Because it's cheap and readily available at most every place we stop.

Sure it's toxic but considering how many thousands of gallons of blue washer fluid get spread all over our highways every year a few more gallons down to sani station dump should not be a big deal :B

My Rv tech said just put a hand full of salt in there. I ask about corrosion. He said urine isn't?

Why do people use windshield washer fluid (that is toxic) when there is a product already made that is not toxic? Surely the $2 difference is a small cost.

I would use anti freeze to flush maybe water it down a bit.Windshield
washer fluid is what I put in the traps at the cabin.I would make sure there is some in there as the gate valve is a low point and you don't
want that to freeze. Good Luck.

I guess I have to explain myself. I'm looking at the future camping. My tanks aren't enclosed, I plan on using bottled water and not using my gray water tank but a wash tub. Just using the black tank for what it's meant for. Dumping at night is out of the question as I'll be boon docking. Flushing with anti freeze sounds doable. I guess the ? is how strong of a mix poo vrs anti freeze.

I just dump.....

I can't really see any reason not to use RV Antifreeze, so that's what I use.