Alkalinity, Total
Desirable Range 50-150 mg/l as CaCO3
Acceptable Range Above 20 mg/l and less than 400 mg/l for ponds Above 10 mg/l for hatchery water (measured as CaCO3)
Total alkalinity (TA) is a measure of the concentration of bases (typically carbonate and bicarbonate) in the water that provide buffering capacity.
The units are milligrams per liter (mg/l) as calcium carbonate.
TA below 20 mg/l limits primary productivity in water, and ponds with such water benefit from lime.
See our publication MP360, Farm Pond Management for Recreational Fishing, for information on liming ponds.
Application rates of copper sulfate for algae control are based on the TA of the water, and copper sulfate should not be used at all in waters with fish if the TA is less than 50 mg/l.
The total alkalinity of a surface water sample sent to the testing laboratory usually will not change significantly over the 2- to 3-day shipping period.