Help please algae issues

[kien]

You have GFO in your canister filter? Interesting, I've never heard of anyone doing that before. GFO generally works more efficiently when it tumbles at an appropriate rate in a fluidized reactor. I'm not familiar with your canister filter but are you able to see your gfo tumble? How often do you replace your gfo? Ommy experience, if you are using GFO and are still reading high phosphates, that is an indication to me that you are not replacing it soon enough. GFO IS VERY efficient at removing phosphates but depending I'm how much media you have vs your phosphate levels, the media can exhaust very quickly. For example, you may find you need to replace it weekly to get your phosphates down.

As for nitrates, there are quite a few options and you kinda have to pick one method that you feel suites you and your lifestyle. All of the various methods will work if employed correctly. ZeoVit, vodka/vinager/sugar dosing, prodibio, bioPellets. Pick your poison :-)