There's an easier way...
I suspect your case of MR prob'ly wasn't due to the water in your tank unless you either fill with well water--and the well has become polluted...or used the same hose to flush out your holding tank that you use to fill your water tank...or (please tell me you haven't done this) made the mistake of connecting a toilet that isn't designed to use pressurized water to your fresh water system. However, you don't have to scrub out the tank to sanitize the system...and JUST cleaning the tank isn't enough to do it...'cuz 90% of foul water problems don't originate in the tank, but in the plumbing. Follow these directions instead: The following recommendations conform to section 10.8 in the A-1 192 code covering electrical, plumbing, and heating of recreational vehicles. The solution is approved and recommended by competent health officials. It may be used in a new system a used one that has not been used for a period of time, or one that may have been contaminated. Before beginning, turn off hot water heater at the breaker; do not turn it on again until the entire recommissioning is complete. 1. Prepare a chlorine solution using one gallon of water and 1/2 cup (4 oz) Clorox or Purex household bleach (5% sodium Hypochlorine solution ). With tank empty, pour chlorine solution into tank. Use one gallon of solution for each 5 gallons of tank capacity. 2. Complete filling of tank with fresh water. Open each faucet and drain cock until air has been released and the entire system is filled. Do not turn off the pump; it must remain on to keep the system pressurized and the solution in the lines 3. Allow to stand for at least three hours, but no longer than 24 hours. 4 Drain through every faucet on the boat (and if you haven't done this in a while, it's a good idea to remove any diffusion screens from the faucets, because what's likely to come out will clog them). Fill the tank again with fresh water only, drain again through every faucet on the boat. 5. To remove excess chlorine taste or odor which might remain, prepare a solution of one quart white vinegar to five gallons water and allow this solution to agitate in tank for several days by vehicle motion. 6. Drain tank again through every faucet, and flush the lines again by fill the tank 1/4-1/2 full and again flushing with potable water. If you do this once a year, preferably as a part of regular spring recommissioning, your onboard water will be as good as any coming of any faucet on land.
