Pressure washing the batt compartment

I have 6 batteries in my compartment. I use a hose with low pressure/flow and flood the batteries and the tray. Then I pour baking soda on the batteries and the areas of the tray i can get to. Wait 30 minutes and wash down the whole thing. Coach now 10 years old, tray and batteries look new. When the batteries dry I spray the terminals with purple protector stuff, that's it.