Reactor + Algae Help

[HidingReefer]

Hi guys,
3 Days ago I received by BRS dual reactor for my 90g
Im running Carbon and GFO on it.
Algae was starting to grow on my glass and in other places in my tank.
So I got the reactor.
I've got a problem. The algae on my glass isn't going away, in fact it's still growing. If im running the reactor, why is algae continuing to grow? Is it that I need to wait, the GFO isnt working, or the reactor isn't working

Thanks

 

[thegrun]

What are your nitrate and phosphate levels? If your phosphates are very high it can exhaust GFO overnight and you will likely need to change it often until you get all the phosphate trapped in your rock, sand and water removed. Neither GFO or carbon will help you with nitrates if that is the source of your problems.

 

[HidingReefer]

According to my test kit my nitrates are .25 ppm, which i think is low..?
Also this tank was started with all dry rock. I don't have a phosphate tester oin me, so I dont know that. Also if it is my nitrates, what can I do to lower them. I barely feed my fish as I only have 1 chromis in there, the tank is 72 days old