BRS GFO

[Coleus]

So my phosphate spike to .11 with hanah test and i bought some GFO pellets from bRS. Base on my tank volume, I need 2.77 cups. I don't know why it is too much as only see ppl with large tank only run about 1 cup.

Should i do 2.77 cups?

Thanks

[untamed]

Well... How much you need is dependent on how much overall phos you have and how quickly you want to reduce it. The media will only absorb a certain amount, then it is "full".

It becomes a question of how fast you want the phos pulled out, and how long you want the media to last before you have to change it.

[whatcaneyedo]

I'm one of those people. My system is roughly 220gal and I just change out a cup of BRS GFO once a month. I only have to clean the glass 1-2 times per week and my macro algae barely grows.

Start with a small amount and keep checking. If you discover that your levels are not dropping or continue to rise just add more.

[lastlight]

I'm a little less technical about how I go about it. I started off following BRS' instructions and the HC stuff is expensive. I just decided my maintenance amount would be 1 cup per month regardless of levels. Actually I don't even test them. When I notice the algae on the front glass comes back strong in 2 days I usually change it out. So far once a month is roughly when that happens.