If Cutrine Plus Algaecide is used in the correct areas and according to the product label it will not kill fish. The product label states not to use this product in waters containing Koi and Hybrid Goldfish and it is not intended for use in small volume, garden pond systems. 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 hazard, do not treat more than ½ of the water body to avoid depletion of oxygen due to decaying vegetation. Wait at least 10 to 14 days between treatments.
 
This is the verbiage from the product label:  This product may be toxic to trout and other species of fish. Fish toxicity is dependent upon the hardness of water. Do not use in water containing trout if the carbonate hardness of water does not exceed 50 ppm. Do not use in waters containing Koi and hybrid goldfish. Not intended for use in small volume, garden pond systems.  
 
Application rates of Cutrine Plus Algaecide range from 0.6 to 1.2 gallons per acre foot of water treated depending on what type of algae you're treating for.  The exact rate will depend on the specific issue you're treating for.  Please see the product label for complete application instructions.

Answer last updated on: 01/19/2023