Most of my phyto was growing by leaps and bounds when the cold snap just hit killing it...Still about 2-3 from edge of pond green all the way around..Water clarity is about 2-2.5 feet..I had this happen last year and the water turned tea brown with zooplankton but it did recover...Is this going to be an annual thing? I have never had it result in a kill...pond is 3/4 acre and 3 years old with the full food chain of fish..Thanks, David.