[RobertB]

They probably don't even sell evaportive coolers in CT, and the season is wrong, they are disappearing from the stores here until next spring...

But, they sell cheap cans of asphalt spray to stop leaks in the bottom of the coolers. Ace Hardware, Blowes, or Home Defect should have some.

I'd guess it's the same as the stuff sold on TV, only a LOT cheaper. If they have Wallgreens Drug stores there, look for the "as sold on TV" isle.