RJ's Beginner Guide to Holding Tank Maintenance


Holding Tank Maintenance
Black Water Tank
The holding tanks can get dirty over time, so it's important to practice preventative maintenance. Let's start with the dirtiest one: the black tank. We don't want to use harsh chemicals in the black tank because that could kill the good bacteria that breaks down solid waste. To keep this biological system working well, make sure to prime it with water and add black tank treatment when you first start using the black tank. This will help control odors and break down waste material and toilet paper in your holding tanks.
After every time you empty the black tank, use your Black Tank Flush to guarantee that the solids reach the sewers. If your monitoring system indicates an incorrect level of the tank, double the amount of black tank treatment used and flush the system a few times to resolve it.
Grey Water Tank
Overtime, solids can build up in the grey tanks as well. You're probably asking where these solids are coming from. And there are a couple different contributors: the first is bar soap (that generally has clay in it), building up on the side walls of your tank overtime; secondly, when you wash dishes and fats/oils go down the drain, they solidify on the tank walls as well. To avoid this, before you put your dishes in the sink, scoop out as much of the stuff off of them as feasible and use a sink strainer to ensure that large chunks do not enter the tank. It's a good idea to add gray tank treatment if you're having problems with the tank monitoring system displaying an incorrect level. The majority of black tank treatments on the market may be utilized in gray tanks, but double-check the directions to make sure.
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Fresh Water Tank
Now, let's discuss cleaning freshwater tanks. Even these need to be drained and sanitized periodically; when your water starts to smell bad, it's time to take care of the problem at its root. Although some people say using bleach is the best way to clean a tank, there are eco-friendly products that don't contain harsh chemicals and work just as well (if not better). To begin, fill a 5 gallon bucket with sanitizer and connect a short hose to your fresh water inlet. Set the Nautilus system to sanitize and then it will pull the solution from the 5 gallon bucket into the freshwater tank. Fill the holding tank with fresh water to 95 percent capacity and let it clean the tank walls for 12 hours. After the time is up, empty the tank and you should be good to go for another 6 months or so.
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Water Heater
The manufacturer of your water heater is probably Suburban or Dometic. And the size of the tank varies depending on the type of rig you have, but it's likely a 10 to 12 gallon system. No matter the type or brand of hot water system you have, it's critical to understand that the pressure for the system comes from the cold water supply. There are many systems that use dual heating methods to enable you to heat water with propane or electricity. When your system is powered by propane, a LED indicator will turn on letting you know there's no flame. When you turn on the switch, the light should be illuminated. If it does not turn off within a few seconds, this indicates that the ignition process was unsuccessful. If this occurs, it likely means there isn't enough propane or no propane at all.
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Water Heater Maintenance
Your water heater should last for decades but it will request some maintenance annually. Start by making sure your electric and gas heat switch is off. If it was on make sure you allow it to cool down before touching it. If you need to work on it right away, turn on the hot water and allow it to drain out, after 12 gallons the tank will be filled with cold water. The last step is to reduce the pressure in the tank, and there are two ways you can do this. The first way would be to go over to your Nautilus system and turn it to winterize mode; this will cutoff the tank from city water. Or, my preferred method: simply disconnect city water from the RV completely, then turn on a faucet and bleed off pressure until no water comes out.
The anode rod can be removed with a deep-well 1 1/16 inch socket and at least a 3 inch extension. The amount of minerals and hardness of your water entering the tank will determine how quickly the anode rod is consumed. Once it's 50% gone, it's time to replace it. The anode rod wears away over time, and it's necessary to replace it yearly if you're using the RV full-time. Otherwise, every 3-4 years should suffice for more recreational users. It's always a good idea to keep a spare anode rod on hand just in case. If you commonly find yourself in areas with hard water, it will reduce the lifespan of your anode rod. To prevent this, I recommend adding a water softener right next to your water filtration system.
There are two types of Anode Rods: Magnesium and Aluminum. If you have a Magnesium rod, over time you may notice a rotten egg smell emanating from your water heater. This is due to a chemical reaction taking place from the sulfides in the water reacting with the magnesium anode rod. This is why I strongly recommend finding an anode rod made of Aluminum and Zinc instead; it doesn't interact with any sulfides or trace minerals in your water so you'll never have the rotten egg smell.
Before reinstalling your old or new anode rod, it's a good idea to use a water hose with a hot water heater extension to clean out any built-up minerals in the tank. You should then cover the threads of your anode rod with teflon tape and then begin screwing back in by hand (to ensure you don't cross-thread) before finishing up with your socket.

In 2021, I uncovered the ultimate way to take my family of four on thrilling excursions around the country without having to forgo our everyday comforts: RV travel!
I am thrilled to be able to share with you the unique experiences and lessons I have learned on my RV trips, alongside a couple of other endeavors I am passionate about: DIY projects, F.I.R.E., and useful life hacks.
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