Yet one more round with the pond.

It hadn't cleared appreciably, and new green algae started growing. Arrgh!f

This is where I put on my water chemistry hat and bite the bullet and get the (fairly expensive) phosphate remover. Or, as we say in the marine reef biz, don't bother getting a test for phosphate. If you've got algae growth, you've got excessive phosphate and no ordinary test will show it, because it's bound up in the algae.

So we killed off a megadose of algae, and here is bright green new algae within 12 hours. Speed of