Can I leave my gray tank’s release valve open all the time?

Ah, another frequent question. We recommend that you leave all (and, for certain, your black tank’s) tank release valves closed until you are ready to empty the tanks.

Why? If you leave the valves open, water or liquid slowly trickles out, leaving behind solids. Even though these may be small (as in gray tanks), they can accumulate over time, creating mounds and piles of rotting waste.

The only time we might leave open a gray tank valve would be while we’re doing laundry. However, unless you’re using more than your gray tank’s capacity, keeping the valve closed during this time is a great way to achieve 100% capacity before emptying, ensuring a nice “clean flush.”

Jim & Debbie Tome, Owners

Hi, we're Jim and Debbie Tome and we're the owners of Kleen Tank LLC, the nationally-recognized and largest professional network of RV tank cleaning service provider.

We've been RVers like you since 2004 and have traveled all over the U.S. in our Airstream travel trailer. We started the business about twelve years ago and have cleaned tens of thousands holding tanks in thousands of RVs. From tiny weekend travel trailers to monstrous fifth wheels to luxurious motorhomes, we've seen just about every situation there is with RV holding tanks and waste systems.

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