I have 55 gallon reef with 15 gallon sump. Sand bed is maybe 4 years old and I removed 1/2 inch to 1 inch 6 moths ago. Current DSB is 3 plus inches.
I have a phosban reactor and use 1 cup of GFO monthly. However, my question, is how do I know when GFO is completed. I understand, I can test, but I don't see results using GFO, so is it possible that it is absorbing within days, rather than weeks?
My nitrates are over 20 and phosphates are undectible by Salifert test kits.
I already do large water changes and see changes immediately and then a few days later, nitrates are over 20. Phosphates with Salifert are undectible.
So I am trying to avoid a future problem. I already have low bio load and predict that it is my sand bed again. However, last time, I had to break down tank, to get to remove sand under rocks.
Corals (SPS and LPS are doing great).
This time, I am trying the GFO and may try NP bio pellets ( from Dr. Harry Lopez thread ) in future. I have done much research on carbon dosing, so my current question, is just "is it possible that GFO only lasts a short time ( 1 or 2 weeks), when my sand bed is leaching nitrates."
Thank you,
I have a phosban reactor and use 1 cup of GFO monthly. However, my question, is how do I know when GFO is completed. I understand, I can test, but I don't see results using GFO, so is it possible that it is absorbing within days, rather than weeks?
My nitrates are over 20 and phosphates are undectible by Salifert test kits.
I already do large water changes and see changes immediately and then a few days later, nitrates are over 20. Phosphates with Salifert are undectible.
So I am trying to avoid a future problem. I already have low bio load and predict that it is my sand bed again. However, last time, I had to break down tank, to get to remove sand under rocks.
Corals (SPS and LPS are doing great).
This time, I am trying the GFO and may try NP bio pellets ( from Dr. Harry Lopez thread ) in future. I have done much research on carbon dosing, so my current question, is just "is it possible that GFO only lasts a short time ( 1 or 2 weeks), when my sand bed is leaching nitrates."
Thank you,
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