gray tank vibe 6504

[geo m]

We have a 2013 6504 vibe trailer with a 30 gal gray tank under front for bath.It has a 60 gal gray tank over axle for galley.This seems to be counter productive since we need far more capasity for the shower than for the kitchen sink.My question is :can these tanks transfer between one from the other? There is a cut off valve at the black tank before it reaches the drain line:therefore we are not combining the black water with the gray water.The owners manuel is generic,so it does not cover the valve at the top of the black water tank.I hope that this message makes sense as I wrote it.Any advice would be appreciated.

[ependydad]

I'm sure smarter people will be along shortly who have actually done this. As long as both gray tanks have separate pull handles and share a sewer connection, it's my understanding that you can get a vale like this:
http://www.amazon.com/Valterra-T58-T.../dp/B000BGHYJS

You twist it onto the sewer fitting. When you're ready, you can leave this closed but open both gray tank handles to equalize the water between the two tanks.

I'm surprised you have such a large tank. Is your camper advertised as having 90 gallons of gray water capacity?