Forum Discussion

boss302's avatar
boss302
Explorer
Jan 11, 2014

Snats/Flies in Black Water Tank

We recently stayed in a RV park in Ft. Myers Beach and there were snats or flies living in the sewer pipe in the ground. While we were there we noticed that these pests would come up thru the toilet when we flushed. We have since moved on but are still getting them whenever we flush. Apparently they have made a home in there. Does anyone have any ideas of how to get rid of these snats/flies. We would greatly appreciate anyone's help.
Class A
  • Clay_L's avatar
    Clay_L
    Explorer
    Jan 11, 2014
    They may have gotten in through the roof vent.
    The larvae can come in through the hose to the gray water tank. We have had them there and they do not have a problem getting through the trap in the shower. They live in the gunk coating the tank walls and waste lines in the RV.
  • hooligan's avatar
    hooligan
    Explorer
    Jan 11, 2014
    FWIW: We once stayed at an RV park in a pecan groove. I picked a bag of nice looking pecans (Off the Ground-duh!!) A few days later, opened the bag and a million bugs flew out...won't do that again...
  • boss302's avatar
    boss302
    Explorer
    Jan 11, 2014
    Thanks for the suggestions. We did have the valves closed and opened only when we wanted to dump but they still came up thru the hose. Will try some of the suggestions and cross our fingers.
  • 1BryNelson's avatar
    1BryNelson
    Explorer
    Jan 11, 2014
    Fill the tank to 3/4 full, top off with big heavy dose of bleach, 1 quart per 40 gallons. Drive around, If possible do this for half a day being sure to do lots of turns snd braking to reslly slosh it around. Dump. Tide works also snd reslly ccleans the tank up. Cold water getd rid of suds.
  • Executive45's avatar
    Executive45
    Explorer III
    Jan 11, 2014
    Any good pest control concentrate will kill them. Dump a quart or so in the black tank, fill it to the top and empty. Problem solved. In the future, when you see the gnats in the sewer pipe, treat the pipe BEFORE you hook up the sewer hose....Dennis
  • ArchHoagland's avatar
    ArchHoagland
    Explorer
    Jan 11, 2014
    I'd use this.


    I use this on my sticks and brick home. It doesn't smell and it kills all bugs on contact.

    I think I would pour three ounces in the toilet, fill with water and flush.

    I'd do that every day till they are gone.
  • BobandShaz's avatar
    BobandShaz
    Explorer
    Jan 11, 2014
    Goldencrazy wrote:
    Why I only open valves to dump and immediately close.


    We learned the hard way!

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