GFO not lowering phosphate

[Lionfish hunter]

I’ve used an entire gallon of the high capacity brs gfo over the past month and it has done exactly nothing. Using media bags in sump where there is the most water flow. I started a reactor yesterday with 2 cups of seachems gfo and my level is exactly the same 24 hours later. I did a 1/3 water change 3 days and my phosphate went from .24 to .17, and has stayed at .17. I have tested every day for a month. People say the rock leaches phosphate back into the water as it equalizes the level but if that were happening, my phosphate level after the water change would have gone back up some. It has stayed steady at .17 after the water change. I have never used gfo before, what am I missing here? The only algae in my tank is coraline and the algae that grows on the walls. I am sick of all the algae i have to clean off the glass, which is the motivation to lower the phosphates. My nitrate level has been around 1-2 ppm steady for over a year, do I need to dose nitrates? Even if dosing nitrates helps, why is the gfo not doing anything…

235 gallon aquarium. 2.5 years set up. Lots of acropora and montipora.

 

[Pistondog]

I dont think lowering the phosphate from those levels will help your algae problem. The level you need to get to will also hurt your corals, they need po4 too.
Minimize your light, manually remove or try some fluconazole.

 

[areefer01]

Just to get clarity. You are stating that you put 2 cups of Seachem GFO into a reactor an saw no change in 24 hours? You tested phosphate, installed the reactor, let it run for 24 hours, tested again, nothing? What was the phosphate reading before and after? Ignoring water change, reactor, or bag did you run a series of tests at the same time daily to see how the phosphate is trending day by day?

Assuming you have the reactor setup, gfo gentle tumble, and water passing through 24 x 7 you should have seen a drop in the phosphate. At least that is what I usually see in as fast as 24 hours.

 

[Uncle99]

Are you certain your test is reporting accurately?
Phosphate, because there’s so little, is sometimes hard to measure, many kits can’t read below .2ppm ish.

I got fooled like this for months, until I started measuring Phosphorus in PPB with the Hanna. All the time it was 0.06ppm, not .25ppm.

Just a thought.

 

[Lionfish hunter]

I dont think lowering the phosphate from those levels will help your algae problem. The level you need to get to will also hurt your corals, they need po4 too.
Minimize your light, manually remove or try some fluconazole.

I dont think lowering the phosphate from those levels will help your algae problem. The level you need to get to will also hurt your corals, they need po4 too.
Minimize your light, manually remove or try some fluconazole.

My millipora haven’t been doing great and I think it might be the phosphate. It was .3 forever. Down to .17 but it only goes down when I do water changes. I need the light for the acros.

 

[Lionfish hunter]

Just to get clarity. You are stating that you put 2 cups of Seachem GFO into a reactor an saw no change in 24 hours? You tested phosphate, installed the reactor, let it run for 24 hours, tested again, nothing? What was the phosphate reading before and after? Ignoring water change, reactor, or bag did you run a series of tests at the same time daily to see how the phosphate is trending day by day?

Assuming you have the reactor setup, gfo gentle tumble, and water passing through 24 x 7 you should have seen a drop in the phosphate. At least that is what I usually see in as fast as 24 hours.

The level moves very little day to day. Started .3 a month ago. Has only ever gone down after water changes. .17 phosphate 24 hours ago and .17 24 hours later.

 

[Lionfish hunter]

Are you certain your test is reporting accurately?
Phosphate, because there’s so little, is sometimes hard to measure, many kits can’t read below .2ppm ish.

I got fooled like this for months, until I started measuring Phosphorus in PPB with the Hanna. All the time it was 0.06ppm, not .25ppm.

Just a thought.

Oh you aren’t kidding about getting fooled with tests. They are awfull. I am using hanna which I have had really bad problems with in the past depending on the reagent batch. But it seems to be reading precisely. Icp 2 weeks ago showed about .1 higher than Hanna. The nyos shows .1 but I don’t trust nyos at all.

 

[Pistondog]

My millipora haven’t been doing great and I think it might be the phosphate. It was .3 forever. Down to .17 but it only goes down when I do water changes. I need the light for the acros.

Why do you think 0.3 ppm is harming your coral?
Likely not elevated po4, imo.

 

[Lionfish hunter]

Why do you think 0.3 ppm is harming your coral?
Likely not elevated po4, imo.

All my other numbers are fine per icp. It’s the only thing I can pinpoint as being not ideal. All the other acros are doing great. It is something small they don’t like, impossible to say what. Radions for light at 300-350 par, and they are in high flow areas. I would also very much like to not clean my glass as often as I do. It’s out of control.

 

[Lionfish hunter]

Also running a large skimmer and large refugium with a high output grow light. Chaeto. I do feed a ton, 12 times a day. Which I am well aware will cause elevated nutrients. But it’s not optional for the health of my moorish idol. I am just trying to figure out why gfo isn’t doing anything for me.

 

[Pistondog]

Also running a large skimmer and large refugium with a high output grow light. Chaeto. I do feed a ton, 12 times a day. Which I am well aware will cause elevated nutrients. But it’s not optional for the health of my moorish idol. I am just trying to figure out why gfo isn’t doing anything for me.

Ive used rowaphos in the past in a reactor with success.adjust flow so gfo barely tumbles.p, or mix with carbon to keep it from clumping.

 

[VP616]

Using media bags in sump where there is the most water flow. I started a reactor yesterday with 2 cups of seachems gfo and my level is exactly the same 24 hours later. I did a 1/3 water change 3 days and my phosphate went from .24 to .17, and has stayed at .17

GFO in a media bag, even in high flow, won't do much or last long. It needs to be in a reactor and it needs to gently tumble to prevent clumping like @Pistondog said.

Have you tested your water-change water? RO water? What are the levels on those?

You've got a heavy feeding regimen which I'm assuming largely consists of pelletized foods that contain a lot of phosphorus. The uptake and output simply may not be enough to match the feeding demands.

 

[Lionfish hunter]

GFO in a media bag, even in high flow, won't do much or last long. It needs to be in a reactor and it needs to gently tumble to prevent clumping like @Pistondog said.

Have you tested your water-change water? RO water? What are the levels on those?

You've got a heavy feeding regimen which I'm assuming largely consists of pelletized foods that contain a lot of phosphorus. The uptake and output simply may not be enough to match the feeding demands.

Yes 100$ of brs gfo has done nothing in the media bag. Reactor has been set up for a couple days now. Doesn't seem to be doing anything, but maybe too soon to tell. It is not tumbling because it is full, but its seachems gfo. Larger pellets, they don't clump. 0 tds ro water, and my water changes are the only time I get lower phosphate readings. I certainly pump plenty of phosphates in the water, but is it really possible gfo can’t keep up? I thought it would be more effective considering how expensive it is and how paranoid everybody is on going slowly to not bottom out phosphates.

 

[Lionfish hunter]

Ive used rowaphos in the past in a reactor with success.adjust flow so gfo barely tumbles.p, or mix with carbon to keep it from clumping.

I might give rowaphos a try.

 

[SPR1968]

Rowaphos will work provided you run it in a reactor at a flow rate so it gently tumbles. You will need to change it frequently to start, maybe weekly, if you have a high phosphate level.

Ive used it for years, it can’t not work provided you change it.

These days I used ATM agent green, just because it’s so much easier, just drop some in the display every so often.

But rowaphos is very good.

 

[dadnjesse]

Yes 100$ of brs gfo has done nothing in the media bag. Reactor has been set up for a couple days now. Doesn't seem to be doing anything, but maybe too soon to tell. It is not tumbling because it is full, but its seachems gfo. Larger pellets, they don't clump. 0 tds ro water, and my water changes are the only time I get lower phosphate readings. I certainly pump plenty of phosphates in the water, but is it really possible gfo can’t keep up? I thought it would be more effective considering how expensive it is and how paranoid everybody is on going slowly to not bottom out phosphates.

Have you checked the flow coming out? I would not pack it full it's supposed to tumble. I don't use seachems but I only put around 2 inches of GFO in my reactor and mine will change my Phosphate from 0.11 to 0.03 in 2 days on my 125 gallon tank.

 

[Lionfish hunter]

Have you checked the flow coming out? I would not pack it full it's supposed to tumble. I don't use seachems but I only put around 2 inches of GFO in my reactor and mine will change my Phosphate from 0.11 to 0.03 in 2 days on my 125 gallon tank.

It is fairly heavy so I would need a lot of flow to tumble it. I just have a little 200 gph pump on it. I do have a little bit of brs high capacity gfo left and will try that in the reactor next. 48 hours of the seachem in the reactor will be this afternoon, hopefully it shows some drop because I bought a bucket of the stuff assuming it would work.

 

[areefer01]

Yes 100$ of brs gfo has done nothing in the media bag. Reactor has been set up for a couple days now. Doesn't seem to be doing anything, but maybe too soon to tell. It is not tumbling because it is full, but its seachems gfo. Larger pellets, they don't clump. 0 tds ro water, and my water changes are the only time I get lower phosphate readings. I certainly pump plenty of phosphates in the water, but is it really possible gfo can’t keep up? I thought it would be more effective considering how expensive it is and how paranoid everybody is on going slowly to not bottom out phosphates.

Well this is easy enough to test. Take your test water sample from the outlet of your reactor. Not the display. The water that comes directly out of your GFO reactor. That should read 0 or near 0. Lower than the display anyway.

Test display water.
Test GFO reactor water.
Compare. GFO water results should be lower if not there is your problem.

 

[Lionfish hunter]

Well this is easy enough to test. Take your test water sample from the outlet of your reactor. Not the display. The water that comes directly out of your GFO reactor. That should read 0 or near 0. Lower than the display anyway.

Test display water.
Test GFO reactor water.
Compare. GFO water results should be lower if not there is your problem.

Yes I do need to do this. I should have more reagent in my mailbox and will post the results later.

 

[Lionfish hunter]

Well this is easy enough to test. Take your test water sample from the outlet of your reactor. Not the display. The water that comes directly out of your GFO reactor. That should read 0 or near 0. Lower than the display anyway.

Test display water.
Test GFO reactor water.
Compare. GFO water results should be lower if not there is your problem.

Aquarium water .15, water from the reactor .17. Pretty upsetting results considering how much of this stuff I bought.