Chemical Filtration

Rowaphos is some good stuff. I used it to help control my algae outbreak when I first started my 150G 4 years ago. If you use that, get a very fine media bag to put it in. Rowaphos is fine granules, a coarse bag will just release it into your tank. Like other suggestion, use it in your canister filter if you have one, or water won't pass through it. Before I picked up my Ehiem canister, I tied it to the intake on my return pump to force water through it. It reduced my flowrate somewhat, but it worked great.