Linda from Cleveland, Tx writes
Have about 1/2 acre pond with fish, mostly about 2-6 feet and about 8-10 feet in the middle. Have submerged weeds including what we think is chara and some floating scum or algea.
Diquat Water Weed and Landscape Herbicide should be applied first and then the Crystal Blue Pond Cleaner to clear dead vegetation and muck/scum. Crystal Blue Black Out does not kill anything. It is used as a pond colorant only, and should be applied every 30 days. Treatment of aquatic weeds and algae can result in oxygen loss from decomposition of dead algae and weeds. This oxygen loss can cause fish and invertebrate suffocation. To minimize this hazard, do not treat more than 1/3 to ½ of the water body to avoid depletion of oxygen due to decaying vegetation. Wait at least 14 days between treatments. Per the Diquat product label, it should be applied in the spring or early summer when the weeds are actively growing and when water temperatures have reached or exceeded 50 degrees. Please see the label for complete application instructions.
Answer last updated on: 03/18/2020
