Recently we have been having a few fruit flies in our RV.
There is only one problem though. We don’t have any fruit lying around. We freeze all of ours. Sheri uses it to make me 100% fruit smoothies – more on that later – I’ll post her recipe. I actually feel better when I drink them.
So they aren’t fruit flies.
How to identify RV drain flies
- They are about the size of fruit flies.
- They seem to be congregating in the bathroom.
- They even seem to emanate from the bathroom.
- That ain’t fruit in the bathroom Dorothy!
So before I go further, I have to digress.
People have to live.
They eat, drink, and breath at a minimum.
As a direct result of those eating, drinking and breathing, we pee, we poo, we sweat, and we exhale. Yet, we are so hung up on stuff we fail to really talk openly about a couple of the things that are about 1/3 of the major operations of our bodies. The rest of this article has to discuss things on the poo/pee side.
You’ve been warned!
Back to those flies.
- I did a little research on the web and I’ve found that there exists such a thing as ‘drain flies’. They don’t seem that uncommon. Here is what I’ve learned in the following bullets.
- People don’t think you should leave your gray water valves open (black should always be closed) even when connected to a septic or sewer. It seems some people think you can.
- I saw mention that if you put a trap (a loop in your drain hose) such that there is no direct AIR path that will keep drain flies out. However, I saw one place that said that the drain fly larvae think traps are ridiculous and can swim.
- I saw mention of insecticides, but nothing very conclusive.
- Someone said drain flies are dirty and carry germs although they probably don’t know. However, knowing where they have been, I really don’t want them flying around my face.
- People in many places spoke about RV toilets with overflow returns having them live in those areas.
- Drain flies can get in your RV if your black tank is vented. Ours is not. Honestly I wished it was. Send me an email if you wonder why it matters.
Here are some links to articles on the subject:
Here is what I did…
How to eliminate RV drain flies
- I drained the black tank immediately.
- I then filled it up and had a modest amount of bleach in it ( I do not use this often as I think it is bad to put in the septic/sewers ).
- We allowed this to sit for two or three days and filled up the tank even more.
- I now keep the gray water valves closed as well as much as possible.
Here is what I’ve noticed.
- Flies are gone.
- Flies have never came back.
Here are my conclusions.
How to prevent RV drain flies from your RV
- Bleach is bad for flies (although I can’t say this was the primary thing that took care of them)
- Draining the black tank often is good
- I can’t rule out that bleach killed the flies
- you SHOULD drain the tank often
- Keeping the gray valves closed is a good idea. (Again, it might be better black tank management that is keeping the flies gone)
Here is one belief I have which I cannot prove : You can get drain flies from the RV park septic. This makes sense to me and I can’t help think it is true.
RV drain flies insecticides and preventative chemicals and sprays