Lowering Phosphate GFO

starfish67

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I added a GFO median reactor using the Rowa Phos 10 days ago. I started slow up to 5 hours a day after 5th day I increased it . Still no results it’s been 3 days now I’m running 24/7 and increased the amount in the reactor. Phos are still high .14 how long should it take to drop to a normal range?
 

Isaac Alves

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.14 PO4 ppm is not really that high -- so maybe that sets your mind at ease :) You should see a reduction of PO4 with rowaphos running the next day.What is the normal range for your system? Every system will be different.

So, some possibilities:
  1. Testing kit error -- are you using a titration test or a Hanna tester for PO4?
  2. Did you over rinse the rowaphos?
  3. Did you rinse the rowaphos with something other than RODI water? Tap water will exhaust it.
  4. Is PO4 rising? Or has the rowaphos kept it at a stable repeatable number?
 
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starfish67

starfish67

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Well there isn’t that much of a track record b/c I had to remove fish for cure of ick for 7 weeks dropped from .08 to 0 then after fish returned to display we spiked to 2.4..used Phos E and went back n forth .24 -.15 up and down swings. Then I added the GFO so I can stop using Phos E. My test are good I used both Hanna and Triton Method my last Triton was .24 close to the Hanna. Today Hanna .14 better but really like to get down to .08 again. So I’ll just keep testing next mail in water sample to mail in triton is on 2/24. I’ll run the GFO see if it drops I was told it can drop pretty fast so I was trying to be careful. My Nitrates are .28 as of yesterday I’m feeding less and change water every two weeks 20 gals total water with sump is 150 gallons. Maybe next time we do a 40 gallon water change next Monday. The tank is only 6 months old and I’m doing everything we can to stabilize it.
giphy.gif
 

Isaac Alves

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sounds like you’re doing ask the right stuff.

Coincidently I stopped dosing Phosphate-E and switched to Rowaphos recently. Had a high Lanthanum number on my Fauna Marin ICP results recently. And I was worried a bit about my tangs.

My tank likes to hover between .09-.13ppm PO4.
 

Randy Holmes-Farley

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I personally would not be using GFO at that level, since it seems nearly perfect to me.

How often do you change the GFO and how much are you using in what size aquarium?
 
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starfish67

starfish67

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sounds like you’re doing ask the right stuff.

Coincidently I stopped dosing Phosphate-E and switched to Rowaphos recently. Had a high Lanthanum number on my Fauna Marin ICP results recently. And I was worried a bit about my tangs.

My tank likes to hover between .09-.13ppm PO4.
Then maybe mine is not as bad as think it is being only 6 months old , thanks for your input 👍
 

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