Speede55,
Do your best to flush out the fresh water tank. Most tanks have a drain right on the tank itself, located in a hidden place. Put your garden hose in running at a slow rate, enough so the drain keeps up with the flow of fresh water. After an hour of that, run the fresh water through the pipes and the hot water tank with it's white plastic drain removed. Once you feel you've gotten rid of the pink antifreeze, then you are ready to disinfect the system.
An annual ritual just before the first RV trip of the season, I disinfect our RV plumbing. I add about a half gallon of household laundry bleach into my 41 gallon fresh water tank and then fill to over-flowing. Then I run the bleach solution through all the faucets. I also fill the hot water tank the same way. I then refill the main tank again to maximize the coverage of bleach solution inside the tank.
Many motor homes have a kitchen faucet, a bathroom faucet, a shower, and an outdoor shower. Be sure to work all of them. Run water through all faucets, hot and cold, with enough solution sitting in the traps to freshen them up too. Let the bleach solution sit in your pipes and tanks for 1 to 2 hours, then flush them all out with fresh water from your flushed-out fresh water tank. It will take about a week of regular use for the water to not smell chlorinated. In the Chicago area, the water smells like that year round so the people in my area feel right at home.
Like most RV people, my wife and I use bottled water for consumption anyway, but it's comforting to know our plumbing is safe.
I also fill our toilet and sinks and add some bleach in them as well to bleach them clean. I also bleach both waste tanks the same way. And after an hour or two, I drain and flush them too.
DO NOT let the bleach sit in anything without flushing it for more than 2 hours for the chlorine can degrade the seals throughout your motor home if left in for extended periods. I have been doing the process I described for 10 years now with our rig because our motor home is stored in our garage below our bedroom. I don't want any hint of sewer gas. All the (pink) flushing (if I had any) and chlorine draining I do is discharged on our driveway. Of coarse the process is started with waste tanks last emptied at a dump station as not to discharge anything bad on the driveway at home. Our driveway starts out smelling ever so slightly yuk but ends up smelling like a swimming pool when I am done.
