First 24 hrs with gfo reactor and a huge drop… what now?

[mrpontiac80]

Hi. I have had a few discussions here on lowering phosphate in an AIO tank using media bags and it wasn’t cutting it so I bought a BRS reactor and BRS reg gfo.
I started it last evening with phosphate at .47 ppm using Hannah 1774. 24 hrs later I just tested and got .09 ppm

I used the BRS calculator and came up with 12 tablespoons or .78 cup. My tank is a Waterbox 65.4. So I estimate 50 gallons of water volume.

what now??? Do I turn it off so I don’t bottom out or keep going? My target is .05 I think. But not against lower. I have a mixed reef.

 

[KrisReef]

I'd cut it off and measure the tank again tomorrow to see if/how much it bounced back. If you leave it on, I can't see any way that it doesn't hit zero unless all the media has exhausted itself making the first drop. Let the animals tell you if they mind the swift change, remember the corals like stability. GL!

 

[mrpontiac80]

I'd cut it off and measure the tank again tomorrow to see if/how much it bounced back. If you leave it on, I can't see any way that it doesn't hit zero unless all the media has exhausted itself making the first drop. Let the animals tell you if they mind the swift change, remember the corals like stability. GL!

Thank you. I honestly expected to be in the .3-.2 range. That kinda gave me a heart attack. I like the idea of testing 24 hrs after turning it off.
Is it safe to assume that if 12 Tbsp in 24 hrs removed almost .40 ppm of phosphate, that 6 Tbsp may be closer to .2 ppm removal in my tank? Or does it not work that way?

 

[KrisReef]

Thank you. I honestly expected to be in the .3-.2 range. That kinda gave me a heart attack. I like the idea of testing 24 hrs after turning it off.
Is it safe to assume that if 12 Tbsp in 24 hrs removed almost .40 ppm of phosphate, that 6 Tbsp may be closer to .2 ppm removal in my tank? Or does it not work that way?

Yes, maybe.
If the flow through the reactor is constant, if the 12 tbsp only exposed to concentrations of P that were less than it could have fully removed the 6 tbsp might not have been over worked in the same situation and it might end removing the same amount of P, if it can handle the total concentration it would have provided the same results.

be very careful with GFO. Measure often until you know how your tank will respond.

 

[doubleshot00]

Just for a simple reference I use a 1/4-1/3 cup or rowaphos for a 90 gallon tank to keep mine in check or bring it down. You used to much. Always take the suggestions and cut them in half or a 1/4.

 

[Natural_Reefer]

Just for a simple reference I use a 1/4-1/3 cup or rowaphos for a 90 gallon tank to keep mine in check or bring it down. You used to much. Always take the suggestions and cut them in half or a 1/4.

I agree, you might have used way too much! I am using 4 Tablespoons of BRS GFO for my S400 (maybe 90gal with the rocks and added sump water?). This amount lowers my Phospate to about 0.10-0.14 and stay there for about 3-4 weeks. I think I should increase the amount by a little bit but my tank is doing well so I am a bit hesitant.

 

[mrpontiac80]

Thanks everyone. I am going to turn it off for 24 hrs and retest. May even try 48 hrs. After that I will definitely cut back the quantity to maybe just a 1/4 of what the calculator called for. For a year my phosphate averaged .07-.09 and over the last month or two it just started rising. I tried media bags and they dropped the numbers very little but seemed to keep it steady around .45-.5 ppm.

 

[mrpontiac80]

So almost 24 hours later I just finished retesting my phosphate using my Hannah 1774.
I am now at .15 ppm
So a recap….
Aug 1. = .47 ppm
Aug 2. = .09 ppm after using gfo reactor for 24 hours 12 tbsp gfo as per reef calculator
Aug 3. = .15 ppm after turning off reactor for fear of going to zero.

so what would you guys recommend from here? I would like to stay around .05-.03 I think but possibly lower. Should I restart the reactor but use only 1-2 tbsp? I just don’t want to strip everything out and cause more problems.

 

[Natural_Reefer]

I'd recommend to restart GFO at 1/3 of the dose and keep testing for at least a week. More important, try to keep nutrients imports (i.e. feeding, dosing,etc...) constant so you know how much nutrients the system is producing and go from there.

 

[Randy Holmes-Farley]

I'd watch it for a bit and restart with a small amount as it rises, which it likely will.

 

[mrpontiac80]

So I took everyone’s advice and after 2 days off, I hit .17 ppm phosphate.

so I started over this time with just less than 1/3 the reef calculator dose… I used 3 Tbsp of gfo and mixed it with 5 Tbsp of BRS Rox 0.8 carbon. I will update tonight on what the level is.

 

[Natural_Reefer]

It seems your Phospate isn't going up really fast so hopefully that would be the right amount.
I could be wrong but I think you need to make sure the GFO/Carbon are tumbling too much and cause the Carbon to break down.

 

[mrpontiac80]

It seems your Phospate isn't going up really fast so hopefully that would be the right amount.
I could be wrong but I think you need to make sure the GFO/Carbon are tumbling too much and cause the Carbon to break down.

The carbon/gfo is mixed and placed in between the sponges. To my understanding you don’t want to tumble carbon at all and only tumble gfo so it does not clump up. Being mixed, it can not clump with itself

 

[mrpontiac80]

So I did test this evening and I was at .12 ppm after 24 hours. That’s a drop of .05

 

[Natural_Reefer]

The carbon/gfo is mixed and placed in between the sponges. To my understanding you don’t want to tumble carbon at all and only tumble gfo so it does not clump up. Being mixed, it can not clump with itself

I see, I have the Little Fishes reactor and have the GFO tumbling, separate by the foam then the ROX Carbon. I might try to mixed them and not tumbling to see if it is more effective.
BTW, that is a good drop. What is ur Nitrate?
I don't think 0.12 Phospate is high! Most of successful reefers I know run between 0.05-0.12

 

[mrpontiac80]

I see, I have the Little Fishes reactor and have the GFO tumbling, separate by the foam then the ROX Carbon. I might try to mixed them and not tumbling to see if it is more effective.
BTW, that is a good drop. What is ur Nitrate?
I don't think 0.12 Phospate is high! Most of successful reefers I know run between 0.05-0.12

I will test again tomorrow all my parameters but I average 17 nitrate. This morning my phosphate is .15 so up very slightly but I feed at night and I’m sure more than most. I’m leaving for the full day so hopefully I can maintain an average of .15-.05 or somewhere in between. Right now everything in the tank is looking better!