Should You Leave Your RV’s Holding Tank Pulls Open or Closed?

A lot of RVers leave their gray holding tank pulls open. Is this a great or even good idea? You may not think it’s a big deal, but you could be asking for trouble. Read on to find out why.

This may seem obvious, but NEVER leave your black tank gates or pulls open while you are camping or using your RV’s holding tanks. We should all know that. But what about your gray tank’s pulls?

What’s wrong with leaving your pulls open?

When your holding tank release pulls are open, the tank’s contents are evacuated through your RV’s waste system and out the sewer hose attached to your RV. When your tanks are 90% to 100% full, the liquid forms a vortex in your tank, helping to wash away all of the waste material inside. A full tank empties better than one that is a third or half full.

But leaving a tank pull open allows water or liquid to seep out, leaving any solids behind. In a black tank, that means human waste and toilet paper pile up, creating a mound that will soon clog your black holding tank and cause a back up in your waste system. Yuck!

But there’s no waste in your gray tank

That’s not exactly true. Your gray tank contains soap, grease, food waste, hair, and other stuff that washes off of you at the sink or during a shower. One time, that all starts to stick together into clumps. Plus, your gray tank is the perfect environment for mold growth, especially slime mold.

By leaving your gray tank’s pull open, the water or liquid drains out, leaving this debris behind. It’s not as dire of a situation as leaving your black tank’s pull open, but it can still cause a stinky gray holding tank and even cause build up over time.

When you can leave your gray tank pull open

What about doing laundry in a clothes washer? Even low-water use washing machines can create a fantastic amount of waste water. It’s okay to leave your gray tank’s pull open when doing laundry.

Jim Tome, Owner

Jim Tome, Owner

Hi, I'm Jim Tome and, along with my wife, Debbie, the owners of Kleen Tank LLC, the national leader in RV holding tank cleaning service. 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, I've seen just about every situation there is with RV holding tanks and waste systems. I hope you enjoy our articles; I try to post at least one per week and we've got a great library of them to cover just about every problem. Enjoy!


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