I think it's to early for a plankton bloom that large. Personally I see many limestone quarrys have that heavy green tint to them, so Ii am thinking it is a chemical/nutrient found in the springs that is causing this. Also some streams here in Eastern Ky that are near coal mine activity will also have this green tint. In the other thread when you said your new pond had " green streaking", thats what these stream look like (pluse they have huge limestone boulders the size of cars in the stream. And I am almost 100% sure they have no alge bloom.
Donnie
