Pond Boss Forums INTRO Questions & Observations Why is My Pond Water Green??

shan leads you to believe that phytoplankton is one type or specie of tiny plant. Actually it a whole community of species (many species) often easily as many as 30 to 50 species growing suspended in the water column in one pond. A typical north-temperate lake can have several hundred algal species comprising the phytoplankton community (Kalff&Knoechel,1978). Another extreme was noted by Lange-Bertalot&Meltzin 1996 who identified over 800 algal taxa from just three lakes in northern Europe! So what you probably have is several to numerous different species living as a group suspended in your pondwater. However very likely only one or several are real abundant, the others have rare to scarce occurrance. The prevaling conditions will depend on who are abundant at any given time. Abundances of the different species varies greatly throughout the year again depending on the prevailing conditions. Each species has its own set of conditions that allows it to become abundant. Natures Way.

Running the aerator or at least the conditions being produced by the aerator may favor the current phytoplankton group. Without examining the water for species composition there is no way to be sure what you have. We can only generalize or guess.

As shan says the current operationg conditions of the aerator may be stimulating nutrient production & enriching the phytoplankton. ALSO Internal or External nutrient sources may be feeding it (fertilizer run off from the grass). Different species like different nutrient conditions or concentrations.

Anyway that is what is making your water green. Very likely at least millions of cells per ounce of water. The phytoplankton feeds the zooplankton; so with green water the zooplankton numbers are also high. Zooplankton feed baby or small fish. A few types of adult fish can also eat zooplankton.

How clear do you want your water? Are you willing to sacrifice fish growth and abundance for clear water? The theme here is to fertilize the water to MAKE it green and grow lots of big fish, although that is not the goal of everyone here.

PS It is a common myth perpetuated by aerator sales people that an aerator will produce clear water. Did someone lead you to believe the aerator would clear your water and if not why run 24/7? Obviously it did not hold true in your case! and a lot of other cases!