Originally Posted by vettenuts
Go to RV Geeks and watch their video. They have a Newmar and explain how to sanitize the tank. It is an excellent video.
Be careful on how much bleach. There is a "parts per million" that you need so not to end up with bleach smell in the pipes and tank. The Newmar specification is based on a bleach that is 5% concentration and many of the bleach bottles in the stores are now 8.25% concentration so adjust accordingly.
The siphon method worked like a charm! Thanks for all the advice to everyone!