If you don't like the smell of bleach. Bleach is NOT the only way to sanitize a water holding tank.
1. Thetford makes a fresh water tank sanitizer.
2. Go to any 'restaurant supply house' they have the 'best' sanitizing products that work way beyond what bleach does. Health dept's kinda require they use them!
I do not drink or use water from the holding tank or to prepare foods with. It's a porous not sealed holding tank that takes on the ambient temperature of whatever the out side weather is. Warm=bacteria.
I do clean my fresh tank thoroughly and regularly to keep bacteria and sediment out and at a minimum. Since I do use it to shower!