- Excerpts taken from Bill's Hints -

Black and gray water holding tanks were defined earlier. Both holding tanks, black water (waste) and gray water (sink & shower) are located below floor level. . The two tanks have drain pipes that terminate into sliding gate valves. The cleaner the waste tank remains the better off you are. A clean tank with proper roof vents will eliminate most problems with odor and expensive service work. Remember that most tanks are very functional and drain properly but some will take more work. For a complete understanding of the waste system review the sections on Toilets, Waste Treatment & Odors, and Sewer Hook-up & Dumping.

Bill’s Hints on Holding Tanks

• If you decide to use any tank-flushing product that hooks up to a fresh water hose and connects to the tank or valve system, always install an anti-siphon valve onto your fresh water faucet. This under-$5 investment will protect your fresh water supply from contamination.
• There are three types of tank cleaning devices; those that connect to the valve system and flush fresh water into the system cleaning the exit to the tank; those that attach to the tank and spray fresh water into the tank; and spray wands that are placed into the tank through the toilet. All have their plusses and minuses but at the end of a trip any extra tank cleaning is recommended.
• Clear fittings are available for attachment to the valve system so you can see when the tank is clean.
• Remember to always use RV Safe toilet paper that breaks down easily. Paper can be big trouble in an RV waste tank causing trouble with monitor panel sensors. Paper is also difficult to breakdown so it can add tremendously to clogging problems. Minimize the amount of paper used. Don't put Kleenex or other disposable products down the toilet. Don't put any insoluble material down the toilet that will contribute to clogging or jam your dump valve in the OPEN position.
• Don't let waste dry up in your black water tank. Before storing your trailer it’s best to get the best possible flushing action when dumping the tank for the last time each season. To do this fill the tank and if your unit has been stationary for a long period, drive it around to help agitate the tank prior to dumping.
• Gray water tanks that accept water from the sink and shower need little maintenance but will occasionally need a deodorizer (use the same one you use for the black water tank). Enzyme waste digesters can be used for the gray tank and have the added benefit of keeping the p-traps clear under the sink and shower.