Best Air Pro 35 Water Evaporator Pad

Not long after I installed this I noticed a handful of pale sludge, about the same color as the coating substance on this product, had come out of the drain tube. It seems like maybe the coating on the product washed off and went down the drain tube. I don't know what the coating is or what it does but it could plug up a drain leading to an overflow, which could cause expensive drywall damage. However it didn't plug my drain and it seems to be working properly so I gave it three stars.