how much gfo for 60g cube

[turbo2oh]

I have a good deal of GHA in my 60 cube. I started macro in the fuge and its growing well but the GHA in the display is still growing aggressively. I bought a hannah phosphate checker and it says 0 though I'm assuming its just all being consumed.

I also bought a BRS GFO reactor and am going to start running it today. I'm confused about how much to start with. I've seen 1tbsp per 15 or 20g as a starting point on the forums (with no specific GFO brand). That'd be about 4tbsp.

However the BRS calculator says a starting point is 15tbsp for 60g. Thats quite a difference. I'm considering splitting the difference and starting with 7tbsp, and also doing a water change, any suggestions?

Thanks,
Phil

[firemountain]

I run 1/4 cup for my 65g and I have seen a nice slow decline in my phosphates. It's way under what the BRS calculator recommends, but I have some SPS corals, and don't want to shock them with a rapid decline.

Also...a lot of algae will throw a false positive on a phosphate reading....esp. When there is an algae problem. Which Hanna do u have... The regular one is not as good as the Hanna ULR phosphate checker. I use the ULR and I find it to work well and is consistent.

[turbo2oh]

I run 1/4 cup for my 65g and I have seen a nice slow decline in my phosphates. It's way under what the BRS calculator recommends, but I have some SPS corals, and don't want to shock them with a rapid decline.

Also...a lot of algae will throw a false positive on a phosphate reading....esp. When there is an algae problem. Which Hanna do u have... The regular one is not as good as the Hanna ULR phosphate checker. I use the ULR and I find it to work well and is consistent.

I have the HI713 I believe its not the URL one. Not super psyched about buying another one of these. I figure as long as my macro and GHA are growing I must have a lot of phosphates in there. Hopefully this will at least start to slow it down.