You are absolutely correct! When Walt & I got back from our trip today, I checked the Series 24 deep cycle - which we use for side pulling - and two of the cells were low on distilled water. We added the water and put her on charge for the night. She'll be all set to go come next week for sure. This extreme hot weather we've been experiencing dries the cells over time, even if garaged. Check your batteries at least once a month.