How to Maintain and Clean RV Black Water Tanks

People who don’t know how to clean and maintain their RV black water tanks wind up with messy and expensive problems. Camping units have three types of holding tanks: fresh water, grey water and black water. All are important, but it is the black water holding tank that requires the most care.

Once a black water tank gets stopped up, a camper has no choice but to contact a professional to fix the problem. It’s possible for an individual to fix his own tank, but the results could be questionable and the mess wouldn’t’ be worth it.

Years ago my own tank got stopped up. I asked a neighbor for help. He advised keeping a bucket handy, opening the tank and shoving a broomstick inside.

It worked, but it worked too well. The contents of the tank came gushing out of the opening like Niagara Falls. The bucket fell over, I was unable to stop the flow, and I wound up knee deep in toilet paper, poop and urine. Worse yet, the mess covered my campsite and flowed downhill into the driveway.

The little boy next door thought this would be fun to play in, and I wound up hosing him off as well as myself and the entire site. It took hours, and I had all I could do to keep from throwing up.

You only have to go through this type of experience once to realize you had better make some changes. I did. I learned how to care for my black water tank, and thus avoided further problems.

If you’re an RVer, my unhappy experience should motivate you to learn proper maintenance techniques. You can get help here.

FIRST: Tank monitors on most RV’s are not reliable, especially the older ones. It won’t matter about this as long as you remember to empty your black and grey water tanks every day.

Clean tanks can keep monitors working but there is more to cleaning than just emptying. If your RV has a backwash function, it will pressure wash the inside of the tank. If not, you can purchase a special wand that attaches to your hose. It's awkward to use, but will serve the same purpose.

The RV industry advises campers to use special (and expensive) chemicals to clean and sanitize black water tanks. This is not necessary. If you empty your tank in the morning and pour in some Spic N Span, it will slosh around as you drive and will help to remove leavings from tank as well as its monitor sensors.

If the tank starts to smell, empty it, and then pour Clorox in it. Fill the tank ¾ full and let it sit a bit. Empty it again and repeat. Keep doing this until you see that leavings are no longer coming from the tank. A clear plastic sewer connection will allow you to do this. Do not leave Clorox in your tank for long periods of time because it will damage it. Only use it as described earlier in this paragraph for periodic tank cleaning.

The industry also advises people to use special biodegradable toilet paper. This is expensive and again, unnecessary. Scott 1000 toilet paper works great and is much less expensive. It will degrade just as well and is easier to find while traveling.

SECOND: Tank size varies from unit to unit. Most hold around 55 gallons, but the smaller the RV, the smaller the tank. Smaller tanks need to be emptied more often. Stats for your RV can be found in the manuals that come with it. If you don’t have manuals, you can find this information on the internet or by contacting the parts department of your local dealer.

THIRD: Some black water tanks only fill from the toilet. Others fill from shower and/or bathroom sink water. The latter fill types are good because they always keep plenty of liquid in the tank, but they are bad because they cause the black water tank to fill quickly. Again, your manuals or your local dealer can give you this information.

Most people think that when they hook up at a campground, they should leave the black water tank open. This is exactly the opposite of what they should be doing. These tanks need to have liquid in them so that the contents can degrade. If the sewer line is left open, the liquid leaves and the solids remain. This is how tanks get stopped up.

When you arrive at the campground, empty the tank. Then close the line. Empty it again prior to leaving the site. Use Pine Sol or Spic N Span to sweeten the tank. Fancy deodorizers are not necessary.

Grey water tank lines should also be kept closed. This way, once you empty the black water, you can empty the grey water and it will clean the hose for you.

If you do these things, you should never smell tank odors. If you do, it’s possible you have a cracked tank. This happens for several reasons, one of which is overloading.

Never wait until the tank is completely full before emptying it, even if you are just cleaning it. Water is heavy and tanks are generally made of fiberglass. Too much weight can crack it, especially if it is older.

If your tank does crack, only a professional can fix it. This is a costly but necessary repair. If you are shopping for an RV, be sure to use your nose. If you smell tank odor, don’t buy unless the owner or dealer fixes the tank before you make the purchase.

Proper care may seem complicated, but once you get some practice, you will see that maintaining and cleaning your black water tank is really quite easy. The time, money and upset it will save you are well worth the effort.

Your vacations will be more pleasant, and your RV will be a nice place. Happy Trails!