Based on these Measurements how well is my GFO working?

[jonnybravo22]

Hello all,

Just wanted to toss a few numbers out there and see what you guys think. Before the data, please note that I am working to bring down my P04 levels. However, I am also dosing amino acids and feeding heavily at times, and adding oyster feast nightly, in order to help my corals get their best color.

Below are my P04 readings over the last few days (all results from hanna checker in ppb phosphorus and P04 in parens):

Feb 20: 62ppb (.19ppm)
Feb 22: 36ppb (.11ppm)
Feb 23 (now): 134ppb (.41ppm) (particularly last night i added aminos)

However I just tested the output water from the GFO reactor and that reading is:
Feb 23 (now): 23ppb (.07ppm)


So my real questions are

1. Does the fact that my GFO output is not 0 mean that it's effectiveness is exhausted? Should it be 0?

2. It is a markedly lower number out of the GFO than the general tank reading; would you all replace GFO or assume it is still working well?

Thanks all.

[Felixc395]

I would highly suggest you stop feeding so much. Amino acids and other foods will give corals color in a nutrient deprived system or one where nutrients are needed for the corals very health. I think you'll be surprised how fast your PO4 levels go down if you cut feeding and run GFO. Just run GFO slowly, reducing phosphate too fast can only make matters worse. It makes sense the phosphate levels are less coming out of the GFO reactor. Suprisinfly GFO can be used very quickly in a high nutrient environment, so I wouldn't be shocked if your GFO goes bad within a matter of a day or two.

Just out of curiosity how are your corals doing now? With that high of phosphate I'd be interested.

I wish you the best in your phosphate reduction, I've been there before! :)

[JMLewis]

When the effluent from the canister my gfo is in has po4 I know it's time to change it out.

[M007]

I would highly suggest you stop feeding so much. Amino acids and other foods will give corals color in a nutrient deprived system or one where nutrients are needed for the corals very health. I think you'll be surprised how fast your PO4 levels go down if you cut feeding and run GFO. Just run GFO slowly, reducing phosphate too fast can only make matters worse. It makes sense the phosphate levels are less coming out of the GFO reactor. Suprisinfly GFO can be used very quickly in a high nutrient environment, so I wouldn't be shocked if your GFO goes bad within a matter of a day or two.

Just out of curiosity how are your corals doing now? With that high of phosphate I'd be interested.

I wish you the best in your phosphate reduction, I've been there before! :)

+1, too much food will exhaust most media prematurely.

[jonnybravo22]

I think the Feb 23 result was testing error.

You see i had been filling up my vial with a syringe. However that's the same syringe i was using to dose the aminos. I had flushed it a time or 2, but probably skewed the results?

Just testing the main tank water again and:

Feb 24: 26ppb (.08ppm)

Given THIS result.... GFO used up?