View printable version of this guide.
Disclaimer: Our recommendations when it comes to using your wastewater holding tanks are based on 40 gallon or more holding tanks. RVers with smaller holding tanks should adjust for the size of their tanks.
Key Points:
As a full time RVer, it’s vital that you properly maintain your RV waste water systems, not only because you want to avoid disgusting odors, but also because prevention is the best defense. It’s always better and typically requires less energy and time to avoid a problem than to have to deal with it later. There’s quite a bit of misinformation out there regarding the best ways to treat your tank while living in it full-time, so we’ve developed this easy-to-follow guide that will teach you how to effectively treat your black tank and gray tank as a full-time RVer.
As a full time RVer, the two most likely issues in your holding tanks are: odors and waste accumulation. The best tank treatment for black tanks is a bacteria and enzyme product (like Unique RV Digest-It) that will take care of these issues all at once. Perform the following steps after each dump:
Note: Perform a short rinse after every dump, but every 3-5 dumps, be sure to rinse for 30 minutes (or more) until you see clear water coming out of the tank, but keep flushing for another few minutes. Often, a second wave of waste will flush out that has collected in the corners of the tank. If your RV isn’t equipped with a back-flush system, run fresh water (or gray tank water) following your black tank dump to flush out the residual waste in the discharge hose.
Note: Bacteria in liquid settle to the bottom over time, and to ensure that the correct amount of bacteria is added, the product needs to be well mixed before each treatment.
Everyone has differing ideas on how to properly treat a gray water holding tank. For full time RVers, the method you ultimately choose is your decision, and it should be based on how you routinely camp. What follows are our gray tank treatment recommendations when using RV Digest-It and full-time camping.
RV full timers who camp on sewer hook-up should keep your gray valve open. We know this goes against the grain for some of you who’ve been properly trained to always keep your black valve closed, but your gray tank should be treated differently when on sewer hook-up. In addition to your tank never filling to capacity, leaving your valve open for gray water to immediately drain to the sewer will help keep sensors free of oil and grease and working properly. When greasy, soapy water continually rises in a gray tank with the valve closed, sensors can become coated with the greasy film and misread, but the water will never get high enough to do that if you leave your gray valve open while on hook-up. There are still some treatment processes to consider whether you leave your valve open on hook-up or need to leave it closed, which are described in the Full-time RVing with Sewer Hook-up and Full-time RVing While Dry Camping/Boondocking sections below.
A p-trap is just a dip in the sewer discharge hose so that there is always a small amount of water in the line to block sewer gases from wafting back through the hose and into your RV. These gases can be dangerous to your health as they contain methane, so consider getting the tools you need to always have a p-trap in the line.
Important: In some states, you are required by law to keep your discharge hose off the ground and failing to do so is punishable by hefty fines. Not knowing this can cost unsuspecting RVers their hard-earned money, so please make sure you are aware of all local laws and regulations and collect the tools you need to comply. You can still have a p-trap when you are camping under these rules, but the p-trap must also be off the ground.
The majority of the waste going down your sink, shower, or dishwasher drains should be liquid, so clogs should not be a concern. It’s important to never let solid food waste or any other type of solid waste into your gray tank. But even large amounts of grease (which are technically not solids) can still cause lots of problems, so still strive to limit the amount of grease that goes into your gray tank as much as possible. Here are some ways you can prevent those things from reaching your gray tank:
We know, you thought Unique RV Digest-It was just for black tanks, but it benefits gray tanks too! If you are full-timing it and are not on sewer hook-up, treating your gray tank can relieve tank headaches before they ever develop. Most dishwashing and hand soaps are antibacterial, but this is not what you want to use if you are treating your gray tank with RV Digest-It; antibacterial soaps will kill the bacteria you’re adding with RV Digest-It. We recommend washing your dishes and hands with Dawn Ultra dish soap because it has great grease-fighting power even in the holding tank (which is why we also recommend it as your gray tank deep cleaning solution), but there are things that can still invade your gray tanks, like food debris, that Dawn Ultra cannot address. No matter how well you strain your drain or wipe your dishes, bits of food debris can still find ways to get past your barriers. RV Digest-It will begin to break down these solids so clogs will never become an issue. The bacteria from RV Digest-It will also help control the foul odors that can develop in a gray tank; yes, sometimes gray tank odors can be worse than black tank odors!
Guide: Why You Should Use a High-Quality Waste Digester in Your RV
Important: Only use tank treatments in your gray tank when dry camping/boondocking where you must keep your valve closed; no tank treatment is necessary when you keep your gray valve open on hook-up. If you add treatment while your gray water valve is open, it will just run into the sewer and your tank will not benefit at all.
When camping on sewer hook-up, you need to know the correct ways to use your tank valves because there is a slight variation in how you would use them while dry camping or boondocking.
Let us reiterate again the importance of keeping your black water valve closed even if you are on sewer hook-up. Keeping the valve open is a recipe for pyramid plugs and other problems that are easily avoided by just closing the valve when not actively dumping a full tank. This means that whether or not you are on sewer hook-up, treating your black tank with a good bacteria and enzyme tank treatment (like Unique RV Digest-It) is necessary to break down waste and control odors. This type of treatment is the best way to combat clogs, odors, and misreading sensors all at the same time.
Guide: Why It's Crucial to Keep Your RV Black Water Valve Closed
When on sewer hook-up, it is actually better to keep your gray valve open. Consider what happens in the gray tank when dry camping or boondocking. You keep your valve closed, which means that every time you use the shower or use the sinks for washing hands or dishes, you are adding soapy, greasy water to the tank. Every time you do, the overall water level slowly rises, which means that floating grease and soap have plenty of time to cling to sensors, potentially leading to misreads. Leaving your valve open on hook-up allows greasy water to immediately flow into the sewer, foiling the chance for that grime to stick to sensors. Built-up grease can still be present in the drain lines and on the tank floor even while leaving the valve open, which is why we highly recommend performing a simple, once-a-week procedure to remove that build-up and prevent odors.
Note: Bacteria in liquid settle to the bottom over time, and to ensure that the correct amount of bacteria is added, the product needs to be well mixed before each treatment.
Remember, tank odors can also come from a discharge line that doesn’t have a p-trap in it; you may just have sewer gases invading because you don’t have a p-trap instead of odor-causing grease and grime. You may also need to perform a deep cleaning on your gray and/or black tanks; built-up waste that isn’t cleaned out with regular deep cleaning can also cause odors.
If you are dry camping or boondocking full time and don’t have any-time access to sewer hook-up, it’s crucial that you use a waste treatment product in both tanks to control odors, prevent clogs, and keep your sensors in proper working order.
Using a high-quality bacteria and enzyme treatment product in your black tank is extra important when boondocking because you want the solid waste in the black tank to be as liquified as possible to make dumping easy and hold as much waste as possible before dumping. We understand that boondockers tend to conserve water and not allow as much in either tank so they can go longer without dumping wastewater tanks and refilling freshwater tanks, but avoiding clogs is probably a better goal than a prolonged dumping timeline. This is especially important when camping in high heat to control odors and clogs. Using more water and a good bacteria treatment product (like Unique RV Digest-It) will help combat all potential issues whether the heat is high or just right.
Note: View the guidelines described in The Unique Method as it all applies to full-timers as well.
Not to beat a dead horse, but as we’ve said before, being on sewer hook-up means you don’t need to add treatment products to your gray/gally tanks, but it is crucial when boondocking. As the overall water level slowly rises in the gray tank, floating grease and soap get extended chances to cling to the sensors, potentially leading to misreads. The most effective routine things you can do for your gray tank while full-time dry camping/boondocking are:
As we mentioned earlier, RV Digest-It and antibacterial soaps do not mix well. Antibacterial soaps will kill the bacteria you add with RV Digest-it, so carefully consider which hand soaps and dish soaps to buy to make sure it will not negate the breakdown power of the bacteria. We recommend Dawn Ultra because it does not harm the bacteria and it is one of the best grease-cutting soaps out there, meaning every time this soap goes down your drains, it will help break up grease in the pipes and in the tank.
After dumping your gray/galley tank, complete the following steps to treat your gray tank:
Note: Regular deep cleanings (every 5-10 dumps for full-timers) will help keep tank odors at bay.
In general, full-timers can follow the guidelines of The Unique Method and get lots of great benefits, but certain aspects of the process need to be slightly modified to accommodate the need for using holding tanks full time. Here is a review of The Unique Method habits with a little tweak or two for the full-time RVer:
Note: Refer to our guide on How to Use Rinser Wands and Other Rinsing Tools.
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You bought your RV so you could enjoy life and spend time with family and friends. The last thing you want to do is waste precious time and money on fixing wastewater holding tank problems. Keeping your tanks in peak operating condition doesn’t have to be hard, confusing, or expensive if you follow our proven process: The Unique Method.
The Unique Method is a comprehensive tank care plan that we developed after years of conversations with real customers facing real problems. The Unique Method provides you with simple, preventative steps to stop odors, clogs, and sensor problems before they start so you can spend less time worrying about your holding tanks and more time enjoying the freedom and adventure of RVing. Try it yourself and see why thousands of campers trust their RVs with The Unique Method every day.
If you need more help with anything covered in this guide or simply have a comment, we’re here to help you anytime!
