Consider getting a "orthophosphate" test PO4 It is a better indicator of whats available for algae and aquatic plants than a "total" phosphate reading.You can have a high ortho but a low total or a high total and low ortho. Just using a total can misslead you.As far as the "green" also consider sending Kevin Ripp at AquaFix www.naturalake.com a representitive sample and they will let you know what is going on in your water. Also which bacteria product and rates to accomplish your goals.