Filamentous algae and planktonic algae are the most common types of algae present in ponds.



Out of various forms of algae, Planktonic algae are an integral part of food chain in the ponds. It is because of its excess that the pond gets its distinctive soupy pea green color. Filamentous algae are the hair-like stingy algae that can be typically seen on rocks and on the surface of mats during summer and spring seasons.

Life cycle of Algae

Algae uses oxygen during night for continuing its cycle of life but when it grows in large amount, the water of the pond gets devoid of oxygen, thus killing fishes. There are three factors that lead to blooming of algae: Excessive sunlight, Excess nutrients, and low levels of oxygen. The nutrients may come from various sources like animal and fish waste, decaying or dead vegetation and fish food in addition to fertilizer run offs and those from pastures and farms nearby.

All these sources give out sufficient phosphorus and nitrogen needed for growing and blooming of algae. Ponds situated in direct sunlight exposed areas or the ones that experience poor levels of oxygen are likely to suffer from problems related to algae. High waste levels in still and stagnant ponds lead to depletion of oxygen required for its breaking down.

As a first step, we should not look upon algae as a real problem. It is a mere symptom that there is a problem in the pond and that it has been out of balance. Algaecide can be used to temporarily get rid of this problem, but it is not a permanent solution because when the algae is killed and left for degradation itself, it will fuel re-growth. This can even cause depletion in oxygen and kill or stress fishes.

Long Term Solution For Algae Growth

An ideal approach to use algaecides is to use them as pre-cursors for a long-term approach as discussed below:

A better approach is to keep the causes of algae growth under control that includes oxygen, sunlight, and nutrients. Improving the levels of oxygen in the pond can be possible with pond aerators and pond fountains. Oxygen infusion can invigorate the bacteria to do their job efficiently and to keep the circulation of water in the pond. Reducing the penetration of sunlight can be a difficult task as you cannot control sunlight to enter into the pond but with the help of pond dye and addition of under-water plants, the pond may provide shade to the water and bound the effects of sunlight.

Controlling nutrients in the pond water may be done through manually skimming the waste and debris from pond, removing algae physically, installing a filtration system, and limiting the amount of under-water inhabitants. Pond bacteria are also crucial for degradation and breaking down of all kinds of organic wastes and needs to be used regularly.

Effective control of algae starts with understanding and knowledge of the algae type present in the pond and the causes leading to its growth. Controlling and treating the sources of algae growth can be better managed with proper information and adequate knowledge.