One tablespoon per gallon is not sufficient. More like 1 oz. (3 tablespoons) I also like the suggestion of using dish detergent, its a great surfacant. I may go that way when my half gallon of surfacant is used up. Want to see how much a wetting action there is in detergent? Put a drop in some standing water. We keep a half barrel of water to water seedlings for the garden and it gets mosquito wrigglers in it. A couple of drops and the wrigglers drown.

Russ