I have tried many different versions of grey water systems since I first bought my popup.
My first system consisted of a garden hose Y-splitter, two short hoses and two collapsible 5-gallon water jugs. I didn't like that system because the jugs, if empty, would fly around in the wind. Also, when they were full, they simply spilled onto the ground. I didn't like having closely monitor grey water waste.
In my second attempt, I tried to create a sealed grey water system using two 7-gallon aquatainors and hoses. Since the aquatainors have a threaded cap that can accept a male hose connector, I thought this would work well. However, the system had a tendency to leak due to the different connectors and slightly different lengths of the hoses I cut. So I wasn't pleased with the system. In fact, I ended up just running the hoses directly into the cap receptacle without the male end connector.
The biggest complaint with both of these systems was that once set up, I could not access the water heater since the galley drain is placed directly above it.
My final system (in the pictures to the right) eliminates all the problems of the previous two mentioned and uses PVC piping. I have seen others use PVC piping for their grey water system, but only on Coleman popups. So I was curious to see how it would work with a smaller drain outlet.
I used 3/4" PVC tubing with all the pieces cut to perfect size using my table saw. The system pulls apart into three separate pieces for easy storage. Before deciding which pieces would pull apart for storage, I first checked the entire system for leaks to eliminate those as pull-apart joints. The connections with minor leaks were cemented together using PVC glue.
As you can see, I have a piece of PVC running perpendicular to the trailer from the drain. I designed the system so there would be a slight slope along this pipe allowing the water to drain. It doesn't screw onto the drain receptacle but slides directly over it and doesn't leak. This piece is long enough so I can completely open the water heater door without first removing the grey water system.
I also have a piece of PVC rising from the terminus of the drain pipe just mentioned. This functions as a vent and allows quick draining of the sink.
Then I have a pipe running to the ground with terminates at a T-splitter from which the water runs into the two tanks.
This system consists entirely of standard PVC pipe and fittings which you can find at your local hardware store. It probably cost me no more than $15 with plenty of leftover PVC pipe.
It has performed flawlessly and does not leak. It also received lots of attention from other campers!
The other advantage to this system is that my freshwater system also uses an Aquatainor. So, I fill my freshwater tank with two Aquatainors and when my freshwater tank is empty, I know I will have two filled greywater tanks. 14 gallons in, 14 gallons out. I never have to check to my tanks to see if they're full. I only have to occasionally look at my freshwater tank level.
