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4aSong's avatar
4aSong
Explorer
Mar 25, 2014

Chemicals for Gray Tank

We use Thetford Campa Chem in our BLACK tank and looking to find what chemicals should be added to the GRAY tank to reduce odor.

39 Replies

  • We have a grey tank specifically for our kitchen drain. If it's hot for a while and we can't dump, it can start to smell. Surprisingly the black tank chems don't do a very good job on it but can help some.
  • We have the same stuff as most, but I don't remember the name, by same company as black stuff, for gray tank.
    One thing, never rinse grease into the tank it will stick to the sides etc and it will get all kinda microbes and bugs. Fill the tank and rinse it good. Put chemicals in it. They also make a gray tank deoderizer. Should be on the same shelf at CW and Wally World. The soap from laundry and shower should be enough to clean it up.
    If it still smells, fill and rinse tank and partially fill, when you leave. Add deoderizer and shampoo or some of the new laundry sopas that don't suds much. Empty at next destination. The sloshing will clean it up.
  • Do you scrape food remains down the drain? That could create an odor. If soapy water only, you shouldn't need any chemical.
  • In my camper there is no trap for the shower/tub, it flows straight to the tank. there is also no roof vent. I use the same stuff that is for the black tank.
    I don't have odor in the black tank, as I don't allow the toilet to be used.
  • You should not be having odor from gray tank..The drain traps should be stopping any odor from coming up the sinks.

    Any odor should be vented outside through the roof vent for the tank.
  • When you get gray odor that means it's time to dump. Either that, or you just dumped and the p-trap water was sucked out.
  • Is there any reason not to try what you're currently using for the black tank?

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