Quoted from nathan.bissonette
If you don't need a fuel sump because you drain the fuel tank after every flight.....
Ok,
Why would you drain the fuel after every flight, with or without a sump? Pre-mixed fuel does not go bad that fast: especially non-ethanol, which you really should use if available.
While modern gasoline are much less "shelf-stable" than the gasoline from 40-50 years ago, it doesn't go bad for several months, even without a stabilizer additive(Sta-Bil, Sea Foam, etc).
Plastic fuel tanks do not create condensation nearly as bad as metal ones. If you are concerned about water in the gasoline when you purchase it from the store, I suggest you buy a Mr Funnel. [url]
https://www.amazon.com/Mr-Funn.....p;keywords=mr+funnel[/url]
I have one, have tested it, and it works as advertised. Also, topping off the tank after flying leaves less room for air, so less chance for condensation.
You can also install a fuel/water separating filter on your bird. I have a Polaris PWC filter installed on my bird's fuel line between the tank and the pump. It is see-thru, so any water is easy to spot. You just remove the locking ring and bowl to dump the water/contaminates.
https://www.ebay.com/itm/Polar.....?hash=item486bf42b25