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How Often Should You Clean Your RV Gray Water Tank?

RV Gray Water Tank Maintenance Tips

Your RV gray water tank stores the soapy water from your shower and all the sinks in your RV. When most RVers think of their gray water tanks, they don’t think of them as a place where solids can build up. After all, we’re only storing soapy water in the gray water tank, right?

What’s Really In Your RV Gray Water Tank

Well, the truth is, that when we wash dishes or pots and pans, we often get small particles of food and even trace amounts of oil or grease into the gray water tank. When these trace amounts of oil or grease go down the sink, along with warm water and dish soap, they are liquid. It’s easy to forget that oil tends to solidify as it cools.

When the oil and food particles get into the RV gray water tank, the food particles sink to the bottom, while the oil solidifies into little bits of solid matter. Both accumulate and build up over time to coat the interior of the tank.

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How often you clean your RV gray water tank will really depend on how much you use it. However, in order to drain as effectively as possible, both your RV wastewater tanks should be full before you drain them. By having them full before you empty them, the weight and pressure of the liquid waste will help push out any solids on the bottom of the tank.

Most RVs have tank sensors on the inside of the coach for freshwater, black water, and gray water tanks. When your RV gray water tank sensor starts to malfunction, it’s a sign that your gray water sensor has gunky solids on walls of the tank that are covering the sensor. A malfunctioning gray water tank sensor usually means that your tank needs a good cleaning.

Cleaning Your RV Gray Water Tank

Using water to spray out built-up food waste and particles from the inside of your gray water tank is impossible. The gray water tank lies somewhere underneath the RV shower pan beyond a one-way diaphragm that is designed to keep smelly gasses in the tank and out of the coach.

If you try spraying through this, there won’t be enough water pressure to dislodge the crud. Trying to spray the tank from the tank valve end won’t work either because of the pipe elbows on the way to the gray water tank.

Why Home Remedies Might Not Work

Although there are a few home remedies for cleaning RV holding tanks that are touted around the internet, none are really effective at cleaning the tank. Dish soap and water softener can make tanks smell much better, but it won’t have any effect on the hardened grease and crud on the bottom of the tank. The effect is similar to pouring some water with dish soap and water softener into a greasy pan and swishing it around. It doesn’t clean thoroughly at all.

Say “No!” To Harsh Chemicals

It goes without saying that putting products like Drano into your gray water tank will shorten the lifespan of your plumbing system and kill the bacteria you need to break down the fats and solid food particles to make them into flushable liquid. Only bacteria-friendly products should be used in your holding tanks.

Let Bacteria Do The Cleaning For You

The only way to really clean your gray water tank is to let bacteria do it for you. Certain bacteria produce enzymes that help break down food particles and grease. After you empty your gray water tank, fill it about 1/3 of the way with clean water.

Every 2 or 3 times you empty your gray water tank, use a formaldehyde-free product like Unique RV DIgest It Holding Tank Cleaner or Happy Campers RV Holding Tank Treatment that encourages the reproduction of these enzyme-producing bacteria. These bacteria like to have lots of water, so always be sure to keep your gray tank about 1/3 full so they’ll thrive and happily munch on any organic matter in your tank.

Track your RV maintenance

Make sure you keep track of all your RV maintenance and repairs with an online tool such as RV LIFE Maintenance. Not only can you keep all of your documents in one place, but you’ll also receive timely reminders when maintenance is due to help you avoid costly repairs and potentially serious accidents.

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