So I currently have a dual reactor running carbon and basic gfo I also have a dual refugium with chaeto and calaupra growing and my po4 is 1.22 ppm and was 2.5 ppm last week before I added the gfo. So my question is how long till I replace my gfo cuz I have some sps frags coming tomorrow and I need my phophates as low as possible so would putting some fresh gfo in today help since it's been about 2 weeks since I put the gfo in that's running now?
Question about gfo and phophates
- Thread starter reeferbuddy215
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mta_morrow
Of course I have room for 1 more fish!
Here is what you can do so that you "KNOW", if your GFO needs replaced.
1 - test your tank water.
2 - get a water sample coming directly out of your reactor before it mixes in with the tank water.
At least that's what I do when I am really concerned and want to be sure.
1 - test your tank water.
2 - get a water sample coming directly out of your reactor before it mixes in with the tank water.
At least that's what I do when I am really concerned and want to be sure.
reeferbuddy215
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When I tested my tank it was 1.55 ppm and then I tested right from the reactor and it is 1.46 ppm so a slight po4 drop but I'm worried as I just did a water change 2 days ago and the po4 is higher but I did gravity vac the entire sand bed which hadn't been done in literally years and was almost black so I think I kicked up a ton of crap. Would doing a small 10% water change again today help get some of the po4 out plus change the gfo?
mta_morrow
Of course I have room for 1 more fish!
doing a 10% water change will reduce it by approximately 1/10th. The bigger the wc, the greater the reduction......your call 
Randy Holmes-Farley
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My Tank Thread
GFO with good flow will deplete in a few hours or less at that level of phosphate.
reeferbuddy215
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Wow well it cut my po4 in half in less then 24hrs and I have a 125 gal with a 40 gal dual refugium and sump so I'm just doing a water change and some fresh gfo
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