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Why We Don't Recommend Copper Sulfate Algaecide

Copper sulfate was used many years ago for algae control however there was adverse environmental effects of copper build-up in the bottom sediments when this product was used. Since then and over the last 30 years or so, a chelated (chemically locked in) copper compound was formulated called Cutrine-Plus(available in liquid or granular). The product is far superior to copper sulfate in that it provides a longer contact (killing) time due to its stability to work in alkaline waters. It also provides a longer lasting control than copper sulfate with lower copper dosages being used and requires less frequent applications. Research and field usage have shown a high potential for detrimental environmental effects. In certain waters, copper sulfate is toxic to fish and other organisms. Overuse of this product is common due to its short-term effectiveness. This can result in copper build-up in the sediments leading to a sterile bottom. A sterile bottom will lead to a lack of beneficial bacteria and cause among other things, high algae blooms which in effect, reduces the chances for aquatic plants to grow due to the shading on the bottom caused from the thick algae. When aquatic plant growth diminishes, so can fish growth and survival.

The preferred method and most natural method for algae control is to treat the water with beneficial bacteria such as our all-natural PlanktoniX beneficial pond bacterial cleaner.  Beneficial bacteria is naturally occurring in any body of water, however when the ecosystem is not balanced and there's an excess of organic nutrients in the water supplying nourishment for the algae to grow, is when there is an abundance of algae and other problems (oxygen deprivation, sludge build-up, etc.) in the pond. The beneficial bacteria helps to break down the silt, sludge, decomposing organic matter, increases dissolved oxygen levels and many other great things. For complete information about algae control for ponds and lakes as well as more information about the importance of beneficial bacteria and proper aeration, please read our  information about algae control


In review, copper sulfate:

  • Has short term effectiveness and therefore is often misused and overused.  Copper remains in the pond and does not bio-degrade.

  • Copper sulfate can be toxic to fish and other organisms.

  • Copper sulfate results in copper build up in pond sediments and creates a sterile bottom in the pond.  Besides many important organisms, it kills beneficial bacteria.

  • Beneficial bacteria such as our all natural, PlanktoniX beneficial bacteria pond cleaner, breaks down organic matter in the pond including silt, sludge, decaying plants, etc. into harmless chemicals.   Beneficial bacteria and algae both feed on nutrients in the water available from the silt, sludge, decomposing plants, fertilizers, etc. By adding beneficial bacteria on a regular basis, you increase the beneficial bacteria colonies and therefore have more bacteria working for you to keep the pond clean, clear and healthy.  

  • We recommend the use of our all-natural beneficial bacteria product, PlanktoniX to treat ponds and lakes for algae control and faster organic matter decomposition from silt, sludge and decaying plants & fish.

  • You can use Cutrine Plus which is a chelated copper algaecide that is chemically locked in to kill pond algae. We offer different kinds.