Thanks to you both.

I'm in Wilmington, Delaware (added to profile ).

I think I'll go without for now and see how things go later in the summer when the water gets very warm. Adding some for insurance while the water is warmer than normal would certainly be better (cheaper) than doing it for the whole season.

I might even skip it at closing this year to see how that goes. If this year is any indication, I'll start champing at the bit to remove the cover around now so I should be able to get the chlorine level up before algae is a concern.

Lenny