Dewinterization

The best way to sanitize the fresh water tank is; Drain tank off, refill to 1/3 full. Add approx. 1/4 cup of bleach to 100 gallon capacity tank. Fill tank to 3/4 full. Turn on water pump and all faucets. Pump until empty, refill tank to 1/2 full and repeat pumping through faucets until there is no trace odor in water coming out of faucets(you might need to refill again and re-pump). Refill tank to 1/2 full add water freshener and fill to full. The water will be good to use until replenishment time.
We do this each spring and never drain the tank. Although we average over 60 days a season, the water never stays in the tank very long.