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Anti Freeze in Black Tank

tuna_fisher
Explorer
Explorer
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. I'm sure it depends on how cold it was to get, so let's say 20. Thanks....
2001 GMC DM, 1995 Lance Lite, @005 Eclipse Toyhauler, Toy's!;)
18 REPLIES 18

d3500ram
Explorer III
Explorer III
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.
Sold the TC, previous owner of 2 NorthStar pop-ups & 2 Northstar Arrows...still have the truck:

2005 Dodge 3500 SRW, Qcab long bed, NV-6500, diesel, 4WD, Helwig, 9000XL,
Nitto 285/70/17 Terra Grapplers, Honda eu3000Is, custom overload spring perch spacers.

ticki2
Explorer
Explorer
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 .
'68 Avion C-11
'02 GMC DRW D/A flatbed

Fishcamper
Explorer
Explorer
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).
2011 Chev 3500 SRW 4X4 gasser - 1999 Lance 920

arto_wa
Explorer
Explorer
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
99 F350 4x4 CC DRW 7.3L PSD, 97 Bigfoot 2500 10.6
(11,900#)

89 Duckworth 17' Pro 302

HoodCanalNorth
Explorer
Explorer
My Rv tech said just put a hand full of salt in there. I ask about corrosion. He said urine isn't?
TCing since 1970. 1997 Ford F150 SC 4x4. 2004 Lance 815. E range tires,Rancho 9000 shocks,Timbren overloads.

dks
Explorer
Explorer
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.

kayco53
Explorer
Explorer
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.
2007 GMC 2500hd
2011 Creekside 23RKS

tuna_fisher
Explorer
Explorer
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.
2001 GMC DM, 1995 Lance Lite, @005 Eclipse Toyhauler, Toy's!;)

Old-Biscuit
Explorer III
Explorer III
I just dump.....
Is it time for your medication or mine?


2007 DODGE 3500 QC SRW 5.9L CTD In-Bed 'quiet gen'
2007 HitchHiker II 32.5 UKTG 2000W Xantex Inverter
US NAVY------USS Decatur DDG31

jimh406
Explorer III
Explorer III
I can't really see any reason not to use RV Antifreeze, so that's what I use.

'10 Ford F-450, 6.4, 4.30, 4x4, 14,500 GVWR, '06 Host Rainer 950 DS, Torklift Talon tiedowns, Glow Steps, and Fastguns. Bilstein 4600s, Firestone Bags, Toyo M655 Gs, Curt front hitch, Energy Suspension bump stops.

NRA Life Member, CCA Life Member

tattoobob
Explorer
Explorer
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
2005 Ford F350 SRW 4x4

2000 Lance 1010

markowwes
Explorer
Explorer
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”

d3500ram
Explorer III
Explorer III
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.
Sold the TC, previous owner of 2 NorthStar pop-ups & 2 Northstar Arrows...still have the truck:

2005 Dodge 3500 SRW, Qcab long bed, NV-6500, diesel, 4WD, Helwig, 9000XL,
Nitto 285/70/17 Terra Grapplers, Honda eu3000Is, custom overload spring perch spacers.

Oasisbob
Explorer
Explorer
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?
Oasis Bob
Wonderful wife 3 of 4 kids at home. 1 proudly serving in USAF
2018 Ford Explorer
2001 Bantam Trail Lite B-19

HAPPY TRAILS:)