[NorskeBob]

This is common - venting method for the tanks is not real good. I fill some - let it vent/burp - fill some and let it vent/burg - keep this up till it no longer takes water - water coming out the vent or fill tube.

If you plan on towing with a full water tank - water is about 8 lbs per gallon.

Sanitizing the water tank is a good idea. I do it a couple times during the camping season. I drain the tank when the RV is not in use parked next to our house.