As sure as death and taxes, when the weather heats up the recreational vehicle forums are filled with posts about the awful smell emanating from the RV holding tanks.
I am just starting my 4th year of full time living in my National Dolphin 32D. The last 2 years have been on mostly remote job sites all over Texas – you can read plenty about that in previous blog posts. I can tell you most definitely that I do not care for the smell of raw sewage inside the Old Girl. So what do I do about that smell when the outside temps are 100+ for days on end?
Lets’ dispel some myths, misinformation and wive’s tales about the black and gray tanks to start with.
A healthy septic system uses bacteria to digest the solids and then the ‘clear’ water is dispersed via field line or sprinklers to be absorbed by the soil. Your RV holding tanks are not a septic system. They are holding tanks — just like a chamber pot. There is no need to add any products that promote bacteria growth like Rid X. The one exception is when I am dumping into a newly installed septic system, I will inoculate it with Rid X to jump start the bacteria.
Every holding tank deodorant/sanitizer I have ever seen does more harm than good. Many contain formaldehyde which will kill a septic system dead. Have you ever been in a Porta John during the heat of a summer? That smell of raw sewage and heavy chemicals just nauseates me. If you want that identical blue water type smell, add some of those RV holding tank chemicals.
Management of your RV holding tanks starts with the manner in which you dump and clean them. The black water tank needs to be dumped only when full. It will actually stay cleaner that way because no dried crud is allowed to form on the walls. You should also use a tank washer each time you dump the black tank to clean the walls of anything clinging to them.
Ok, so you say you do that and your tanks still smell to high heaven? Do what I have been doing for years and use the safe GEO method introduced by Charles Bruni. It uses water softener, detergent and bleach. Each and every one of these safe household chemicals will not harm your septic tank and will eliminate the odors and keep your tank clean. The GEO method is simply this:
This stuff is amazing and it works. Buy a couple of boxes of powdered water softener at the grocery store. You’ll find it located with or near the laundry detergent products. I prefer Calgon Water Softener because it dissolves quickly in water. Cheaper water softeners work just as well but dissolve more slowly. Dissolve two (2) cups of the water softener in a gallon of hot water. Then, pour the solution down the drain into the empty tank. Use two cups of softener for each wastewater tank in your RV. The tank’s drain valve should be closed otherwise the softened water will just drain out. Then use the tank(s) normally until it is full and drain it normally. Add a cup of laundry detergent to the black (commode) water tank at the same time you add water softener. This will help clean the tank. The gray water tanks should already contain soap through normal use. Water softener makes the solid waste let go from the sides of the tanks. If you’ve ever taken a shower in softened water you know that after rinsing the soap from your body your skin will feel slick. That’s because all the soap rinses away with soft water. Softened water also prevents soap scum from sticking in the tub. Get the connection? With softened water gunk washes away instead of sticking. The same thing applies to your RV’s wastewater tanks.
I use a clear plastic elbow connector to attach my sewer drain line to the wastewater outlet on my RV. It allows me to see how well things are progressing during a wastewater dump. Before I began using water softener regularly the black water tank’s water was brown, the galley tank’s water was brownish, and the bathroom tank’s water was white. The first time I added water softener to the tanks the water coming from the black water tank was actually black (not brown) and the kitchen tank’s water was also black (not brownish). The bathroom tank’s water remained white. That told me that the water softener had actually done what I had intended for it to do and made solid waste, which had been stuck to the interior of the tanks, let go and drain away. I added water softener (and laundry detergent to the black tank) to all the wastewater tanks for the next few dumps to be certain all the solid waste possible had been cleaned away. The wastewater only appeared black on the initial treatment. I now add water softener and detergent to each tank once after every few dumps to maintain the system.
Too little water softener may not be of sufficient concentration to work effectively. Too much water softener will NOT hurt the tanks. So, if the amount you used didn’t quite do the job, then use more the next time. Don’t forget the laundry detergent.
Occasionally, I pour a half gallon of liquid bleach into each tank to deodorize, sanitize and disinfect them. I add the bleach when the tank is about half full, and then continue to use the tank normally until it is full and ready to dump. I no longer use the blue toilet chemical because it isn’t necessary. I have no odors coming from my black water tank. The chlorine bleach kills the bacteria, which is primarily responsible for waste water tank odor. Generic brand liquid bleach is cheap and very effective.
Let me add to what Mr. Bruni said. I use the Calgon Liguid water softener. It is expensive but it works. I also use Dawn dish washing detergent instead of laundry detergent –especially in the gray tank. It cuts the grease better. Many times I have a limited water supply like now where we have to bring all of my water in from off site in a 300 gallon tank. I am NOT rinsing my tank after dumping simply because I do not have the water to waste. Since I am not cleaning the tank properly after dumping sometimes I do get a little odor. A quart of bleach dumped into the tank will kill the odor immediately.
Recreational vehicle owners obsess and worry about plenty of different things. They aslo spend money on needless items. Follow these tips for managing your RV holding tanks and you will have less worry and keep more money in your pocket.