Copper Sulfate Pond Algae Dosage Calculator
Calculate copper sulfate pounds to dose a pond to a target parts-per-million concentration for algae control, using pond acre-feet.
How This Calculation Works
Chemical pounds equals acre-feet times the target concentration in ppm times 2.72, the standard factor for pounds per acre-foot per ppm. A 1.4 acre-foot pond dosed to 1 ppm needs about 3.8 pounds of copper sulfate. The 2.72 factor converts the concentration and volume into weight.
Field Calibration & Rate Reference Chart
| Surface ac | Avg depth | Acre-feet | Copper lb @ 1 ppm |
|---|---|---|---|
| 0.25 | 4 ft | 1.0 | 2.7 |
| 0.5 | 4 ft | 2.0 | 5.4 |
| 0.5 | 6 ft | 3.0 | 8.2 |
| 1.0 | 4 ft | 4.0 | 10.9 |
| 1.0 | 6 ft | 6.0 | 16.3 |
| 1.5 | 5 ft | 7.5 | 20.4 |
| 2.0 | 5 ft | 10.0 | 27.2 |
| 2.0 | 8 ft | 16.0 | 43.5 |
| 3.0 | 6 ft | 18.0 | 49.0 |
| 5.0 | 6 ft | 30.0 | 81.6 |
Common Questions
How much copper sulfate do I use per acre-foot?
A common rate is 1 ppm, which equals about 2.72 pounds of copper sulfate per acre-foot. Some labels allow up to 2 ppm for severe algae. Never exceed the label rate, especially in soft water.
Is copper sulfate safe for fish?
It is safe at labeled rates in hard, alkaline water but can be toxic in soft, low-alkalinity water where copper stays dissolved. Test total alkalinity before treating. Treat part of the pond first to gauge the response.
Why can algae treatment kill fish?
Killing a large algae bloom at once causes the dead algae to decay, which consumes oxygen and can suffocate fish. Treat in sections and avoid treating the whole pond at once. Aerate during and after treatment.
When should I apply copper sulfate?
Apply early in the morning when oxygen is lowest but the treatment has all day to work, and avoid hot, still afternoons. Watch dissolved oxygen for several days after treatment. Repeat only as the label allows.