I have noticed that when cow manure is added to a pond, the water goes green or green/brown suggesting the growth of
organisms such as cyanobacteria, chrysophytes, cryptophytes and euglenoids, it doesn’t look like water mould.
I find this strange becuase if I add the ingredients of cow manure (ammonium, phosphate, potassium, calcium, magnesium, trace metals and amino acids) to some water, after about two days I have a load of what looks like water mould i.e. the water is orange or grey.
What is it in cow manure which inhibits the growth of water moulds?
(I should point out that I only get the water mould if I include amino acids, but cow manure apparently contains those).
The only thing I can think about is that when you add, cow manure that it is too acidic to neutral for them to grow with a PH between 4.6 to 7.4, when you added the chemicals to the water, they may have been in different amounts changing the PH to a different amount. This could also be the function of Bacterial E. coli or left over enzymes from digestion that kills the Water Mold. I am not really sure which of these it actually is but it could be one of them despite what you may think Foreign E. Coli can be pretty deadly to other organisms. My bet is you have some highly evolved cow bacteria eating your Less Evolved Water Mold having a much shorter evolutionary record. The are highly evolved predators of the microscopic world despite what they do in our bodies. They normally eat cyanobacteria, which is why cyanobacteria still grows in those waters with E. Coli having more evolved defenses but your water molds may not have much defense against them. Cyanobacteria being one of the first bacteria to evolve on this planet around 4 billion years ago, E. Coli are about as old being Bacterial super-predators.