[Bill]

I tried this last year. Phosphates went from 1-2ppm to zero and nitrates went from 20ppm down to 5-10ppm. This took about 3-4months.

It works, but needed lots of carbon to keep water from turning green and cloudy. Needed weekly cleaning and algae falls off the screen when it gets too thick. Can try double screen to help it attach better. I used a plastic screen from Walmart $1.60 ea and 2-23W coil CFL soft white for $6 for pack of 2 from Save on Foods.

Lots more info on algaescrubber dot net