If you don't have a gravity water fill or a winterizing port at your water pump, here's a couple more ways to insert the sanitizing solution.
You can fill your water hose with the the sanitizer, then connect it to the RV.
You can use a pump. I have a $12 drill powered pump and a couple short pieces of water hose (Camco makes them). Mix my sanitizing solution in a bucket and pump into the RV from the bucket. I also use the pump to put fresh water in the RV when dry camping.
Vince and Susan
2011 Tiffin Phaeton 40QTH (Cummins ISC/Freightliner)
Flat towing a modified 2005 Jeep (Rubicon Wrangler)
Previously a 2002 Fleetwood Pace Arrow 37A and a 1995 Safari Trek 2830.