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jbrack's avatar
jbrack
Explorer
Jul 05, 2019

Black Water Tank Treatments

Just curious as to how long it takes for the drop-in holding tank treatment pods take to work? Does it do any good to drop one in if you will be dumping your tank within a few days? Do those things act that quickly or are they meant for longer periods of time between tank dumps? Just wondering if I'm wasting money on these things.
  • If all various odor blocks noted above work properly all the time, and nothing ever goes wrong when dumping tanks, and you never, ever make mistakes when dumping tanks and never spill even one drop of waster water on the ground ever....Then, yes, in that 'perfect' world/utopia, black tank chemicals are not needed.

    However, I don't live in that 'utopia' where nothing ever goes wrong, haha. The world I live in, things occasionally do go wrong. Vents get clogged, water in P traps evaporates enough to allow some odor into the RV, hoses or hose fittings wear out and may leak a drop or two before I can correct the issue. THAT, is why I use black tank chemicals (Odorlos). They minimize the smell, when (not if) something goes wrong or doesn't go exactly as planned.

    Your neighbors will appreciate you taking such precaution, too, when something goes less than perfect and allows some of your holding tank odors to escape (like maybe when a sewer hose has a slight leak, isn't attached securely to a fitting, etc.)

    I don't think its as much about assisting with break-down of solids, cause as already said, that happens at the same rate regardless of chemicals. Its more about minimizing the odors for the times when something doesn't go exactly as planned.
  • "Act" isn't the right word. The pills mostly help with smell. No, I'm not "misinformed."
  • We always use the premeasured thetford tank treatments in our black tanks. We have two tanks so always use 2. The chemical is fast acting and diferent than the ones made for septic tanks as it will breakdown the solids quickly. We always dump when 3/4's full. In the 20+ years we've RV'd we have never had a tank issue like many of our friends who do not use them. Some will tell you that the chemical is just a deodorizer. They are so misinformed.
  • I have found by experience that using black tank treatments is a waste of money, especially if you move your camper opposed to sitting long-term on a season site.

    If your camper is on a seasonal site, then yes. I think the treatments help cut down on odor. But I have found that just flushing the tank keeps odors at bay just was well.

    If your camper is in "transit" (not seasonal), then probably one of the best ways, in my opinion, to keep it clean is to dump everything before hitting the road. Then add about 5 gallons of water and about a half a cup of Dawn Dishwashing liquid. The bouncing on the road and splashing of the water in the tank will clean the tank and keep it from smelling. Do this every time you move the camper from home to campsite, to campsite, to home, and you'll never have smelly tanks.

    Other folks use different kinds of dishwashing liquid, laundry soaps, floor cleaners (like Spik n Span or Mr. Clean products) and even some bleach. Be careful if using bleach, you want to flush your tank after bouncing down the road real good. Bleach is not the best for your dump slide valves and over time can cause deterioration. I use bleach very seldom in the tanks, as Dawn does a great job deodorizing and cleaning.

    I will use the black tank treatments over the winter months when the camper sits idle, with RV antifreeze in the black tank. This is about the only time I use it.

    Holding tanks are not septic tanks. They only hold the contents. If you experience a poop pyramid, filling the tank with water and Rid-x and letting it sit for a month will help dissolve the pyramid and break it down. But as a treatment between dumps, every few days ... nah... you're tossing your money ... literally ... down the toilet.
  • RV Waste Tanks are 'holding' tanks not septic systems
    The 'stuff' will break down just as quickly/as effectively using WATER as it will using 'chemicals'
    Chemicals mast odors......BUT if you have noticeable odors inside the RV then one of the 'barriers' is not working
    Water in toilet bowl..vapor barrier
    Water in 'P' traps....vapor barrier
    Air Admittance Valves...mechanical barrier
    Toilet floor flange ...mechanical barrier
    Waste Tank Vents .....mechanical relief

    Dump waste tanks when 3/4 or more full...weight/volume causes the WHOOSH affect
    Add few gallons of water back into waste tanks after dumping so bottom of tanks stay wet
    Use water.

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