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water_witch's avatar
water_witch
Explorer
Feb 09, 2014

Eeew! Gnats coming from black tank??

I know I saw posts about this in the past but my search here is turning up nothing. Today we have little gnat thingies coming out of the potty from the black tank. What to do? Hate bugs especially in the potty! Anybody had this problem and how did you solve it? Thanks!

37 Replies

  • water witch wrote:
    352 you are kidding, right? ....
    I certainly hope so.
  • Water witch, are you leaving the black tank valve open or closed?
  • 352 wrote:
    Yes I did and this solved it for good. Sometimes stuff gets stuck down there. Reach your arm down the hole as far as you can. When down to the max feel around for anything chunky. Grab it and squeeze it between your fingers until it gets smaller then dump some water in it (After you pull your arm out of coarse}. Do this once a month for regular maintenance. Wash your hands before cooking. I do have a self help video available. Hope this helps.


    Thank your for sharing! The verbal description is enough so I will pass on the video. lizzie
  • 352 you are kidding, right? DH has recently become disabled and I have to do the yucky RVing things now. Which I am normally OK with. But. Not sure I can stick my hand down there and squish around. Will RV repair people do that for a fee? Don't mean to sound like a princess. I am doing the best I can but squishing in the tank may be a bridge too far for me. :(
  • Those are sewer flies. They live in sewer pipes. Some think they a mythical but as you are finding they do exist. They are another reason not to leave your dump valves open when not dumping and expose your tank to the sewer lines.
    Drain tank completely and spray insecticide into tank. Use a full can allow spray to sit in tank as long as possible before using. Fill with water and dump tank. Repeat as required.
  • Yes I did and this solved it for good. Sometimes stuff gets stuck down there. Reach your arm down the hole as far as you can. When down to the max feel around for anything chunky. Grab it and squeeze it between your fingers until it gets smaller then dump some water in it (After you pull your arm out of coarse}. Do this once a month for regular maintenance. Wash your hands before cooking. I do have a self help video available. Hope this helps.
  • water witch wrote:
    I know I saw posts about this in the past but my search here is turning up nothing. Today we have little gnat thingies coming out of the potty from the black tank. What to do? Hate bugs especially in the potty! Anybody had this problem and how did you solve it? Thanks!

    Try to pour some javex bleach in,that should kill anything

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