Galley vs Gray Tanks

[kitt614]

First time RVer here, looking for a little advice that I think will probably be model specific.

DW and I just bought a 2017 Wildwood X-Lite 263BHXL. We've never RVed before, but we are quick learners. We took it out this weekend for a Fri-Sun trip a couple of towns away. Amazing weekend, and so happy that we got the RV.

So over the weekend, we started out not very water conscious. Laying in bed on night one, I started thinking about how we had washed the dishes and realized we were a little heavy on the use - not shutting the water off to suds dishes and such. But that's not so much the issue. I was thinking we would be fine for we weekend trip, but boy that water adds up fast, even once we switched tactics to conserve water.

So on Sun morning, we are packing up, and I realized that the sensor read that the galley tank was full, but the gray tank was near empty (I took a shower that required about 190 seconds of water between wetting and rinsing - but that was the only shower; DW wanted to wait til home). Previously, I had been thinking that the kitchen sink was dedicated to the galley tank, and the gray would be shower and bathroom sink. But, what I noticed was that the bathroom sink was we were bushing our teeth before packing up camp started to back up, and didn't really settle. The shower pan had no water backed up in it.

This makes me think that the galley is for the two sinks combined and the gray would only be shower? Which seems a little odd to me, but I just want to make sure I know for the future. When emptying, the galley definitely ran for a while, while the gray tank really did have nearly nothing in it. Does anyone know if the galley for the sinks and gray for the shower is really the case? I might crawl up under it to see if I can trace the pipes and get a solid answer on this - but I don't really want to crawl under it if I can avoid it.

TL;DR
I have a galley and gray tank. I thought the galley tank was just for the kitchen and the gray tank was for bathroom sink and shower. But the indicator showed galley was full, gray basically empty, and water was backing up in the bathroom sink (but not the shower pan). Is the gray just for the bathroom, and both sinks into the galley? What are the thoughts here?

[CHICKDOE]

Open a drain valve and then let water run down the drains one at a time. If it comes out the tank you’ll know the which tank the drain is plumbed to. Repeat until you get all drains identified.

[kitt614]

That is a great suggestion Chickdoe, thank you! Much easier than crawling in the gravel.