Question: We have purchased a new 5th wheel and previously I read an article that told you how to prepare your black tank with a slicking agent – “Calgon” and hot water – to help the tank remove waste. Do you know the procedure for this application?
Answer: We have never tried it ourselves, but we did find a link to the “Geo Method” procedure you reference. We can’t offer an opinion on this, but here is an excerpt and the link to the full post:
RVs are equipped with waste water HOLDING tanks; NOT septic tanks. Those holding tanks are nothing more than chamber pots which should be cleaned and sanitized after their contents are disposed of. The Geo Method is based on this fact.
DUMP A FULL TANK When camping and connected to a sewer/septic intake, leave the drain valves closed until the tank is full and ready to dump. This provides sufficient water to flush solids from the tank. Leaving the drain valves open allows the water to drain off without flushing out solid waste. That solid waste will collect in the tank(s) and cause problems over time. If your tanks are not full when you are ready to dump them, fill them with fresh water first, and then dump them.
DUMP DIRTIEST TANKS FIRST This means first dump the black (toilet) water tank first, then gray water tanks. This way you will be flushing out the sewer hose with progressively cleaner water.
USE WATER SOFTENER, DETERGENT, and CHLORINE BLEACH Buy a couple of boxes of powdered water softener – Calgon Water Softener preferred because it dissolves quickly in water. 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. Add a cup of laundry detergent at the same time as you add the water softener. Then use the tank normally until it is full and drain it normally. With softened water, wastes washes away instead of sticking.