Forum Discussion

bigorange's avatar
bigorange
Explorer
Sep 30, 2018

Adding a “supplemental” gray tank?

We love the floorplan of our new 5er, but I’m not happy with the holding tank capacity...primarily gray. I’ve thought about replacing the tank with a larger tank, but I’m wondering if it’s possible to plumb another tank onto the existing tank with a high and low connection to equalize between the two and effectively double the capacity,.or would I be better off adding a second tank and plumbing it separately to the galley sink and leave the shower/bathroom sink to the old tank?

Yeah...next trailer we buy the tank capacity will be a top consideration. Floorplan won out on this one at a cost...
Seeking Advice
  • Pirate1's avatar
    Pirate1
    Explorer
    Sep 30, 2018
    I added a second gray tank to my motorhome. It's 35gal. It is situated between the stock gray tank and valve so I can use gravity to fill it and empty. I doubled my capacity. I only use it when primary tank is full. Pull the valve, it all fills up secondary tank, close valve, primary tank ready to use again. Vent on secondary tank is a 1/2" 90deg fitting which the tank came with.
  • dave17352's avatar
    dave17352
    Explorer
    Sep 30, 2018
    How about equalizing your black and gray tanks. I do this on my truck camper with zero issues. Its all sewage.
  • pfidahospud's avatar
    pfidahospud
    Explorer
    Sep 30, 2018
    Not necessarily advocating this, but depending on where and how you camp, sometimes the local trees and shrubs need watered. Just sayin’.

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