Finding the fresh water drain can be like a scavenger hunt......
Can you see all sides of tank? Should be a 'fill' line, a water pump 'suction' line, a 'vent' line and then a 'drain line'. Drain valve could be under RV, inside a compartment, behind a 'panel'. Let the hunt begin :B
Test kit....WHY?
Do you test you house water?
Sanitize
1/4 cup house hold bleach to 10 gallons water
If sanitizing tank might as well sanitize plumbing system by running the bleach treated water thru hot/cold lines
Let sit for several hours then drain/flush/rinse
I sanitize our fresh water tank(s) once....when we first get rid.
After that I don't.
We fill with good treated water source (city water etc.)
We use the water just like we do in S&B House....wash/drink/cook. It's the same water.
We drain fresh water tank if not going to be used with in a month. Then refill with fresh.