Phosphates and GFO, what am I doing wrong?

wintrmte

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Hi All -

First, my parameters:

Phosphates (Hanna test): 0.12
Nitrates (Hanna test): 9.7
200 gal total tank volume, 160 gal DP
My bio load isn't too heavy, I have 1 Naso tang, 2 hippo tangs, 1 yellow tang, 1 flame angel, 2 clowns, 2 firefly fish, 1 bristletooth tang

All LPS coral, and an anemone who has split and is hosting the clown fish..

--

I've been using Rowaphos trying to get my Phosphates down to < 0.5 but it's a winless battle. Everyday the phosphates reads something different.

A couple days after putting in fresh rowaphos, the po4 will read 0.7.. a couple days later, 0.12. It's a winless battle!

I have an Avast Plank auto feeder going two times a day for 1 minute each -- using the Avast Reef Jerky as the food.

According to the rowaphos calculator, I'm supposed to use 84ml to go from 0.12 down to 0.2, but 84ml doesn't even make a dent.

Thoughts on how I can get a handle on this, or am I over reacting and this really isn't an issue?
 

Mr. Mojo Rising

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If you started with dry white rocks, it’s possible that phosphate is leaching from the rocks. It took me over 2 years to drain phosphate from my rocks when I started.
 

Red_Beard

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Sounds like it is working. If it is going from .7 to .12 that is a very large reduction.

Likewise going from .12 to. 2 is an increase in phosphate
 

Uncle99

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GFO is an expensive mop.
I did better just by changing my socks out every 2 days instead of every 4.
Combined with a small daily carbon dose and a lit fuge, can hold me at .2ppm with heavy feeds.
 

Dan_P

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Hi All -

First, my parameters:

Phosphates (Hanna test): 0.12
Nitrates (Hanna test): 9.7
200 gal total tank volume, 160 gal DP
My bio load isn't too heavy, I have 1 Naso tang, 2 hippo tangs, 1 yellow tang, 1 flame angel, 2 clowns, 2 firefly fish, 1 bristletooth tang

All LPS coral, and an anemone who has split and is hosting the clown fish..

--

I've been using Rowaphos trying to get my Phosphates down to < 0.5 but it's a winless battle. Everyday the phosphates reads something different.

A couple days after putting in fresh rowaphos, the po4 will read 0.7.. a couple days later, 0.12. It's a winless battle!

I have an Avast Plank auto feeder going two times a day for 1 minute each -- using the Avast Reef Jerky as the food.

According to the rowaphos calculator, I'm supposed to use 84ml to go from 0.12 down to 0.2, but 84ml doesn't even make a dent.

Thoughts on how I can get a handle on this, or am I over reacting and this really isn't an issue?
Are you mixing up the numbers in your post ? 0.12 is less than 0.5 ppm.
 

rishma

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If you started with dry white rocks, it’s possible that phosphate is leaching from the rocks. It took me over 2 years to drain phosphate from my rocks when I started.
Agree with this, though even live rock and sand will bind and release phosphate. A lot of people experience swings that don’t make sense until things reach equilibrium.

The recommended amounts of rowaphos or GFO cannot account for what is released from the rocks. It takes time for things to stabilize.

Here is my method to lower phosphates…


What I do is add a small amount of GFO in a bag with carbon. I monitor daily or even 2x per day and then add more GFO when phosphate stops dropping. Rinse and repeat. I leave the original bag in and just keep adding small bags (I don’t use a reactor). In find that by adding small amounts I can keep a steady downward trend until I reach my target. Then I start removing small bags in reverse order. This prevents the PO4 from changing quickly and prevents it from rising again after I reach my target. I figure that by going slowly I am removing large amounts of total PO4 from tank, rather than small amounts quickly which just get replenished through release from calcium carbonate surfaces.

I expect the OP forgot a zero next to the decimal in his readings.
 
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wintrmte

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Agree with this, though even live rock and sand will bind and release phosphate. A lot of people experience swings that don’t make sense until things reach equilibrium.

The recommended amounts of rowaphos or GFO cannot account for what is released from the rocks. It takes time for things to stabilize.

Here is my method to lower phosphates…


What I do is add a small amount of GFO in a bag with carbon. I monitor daily or even 2x per day and then add more GFO when phosphate stops dropping. Rinse and repeat. I leave the original bag in and just keep adding small bags (I don’t use a reactor). In find that by adding small amounts I can keep a steady downward trend until I reach my target. Then I start removing small bags in reverse order. This prevents the PO4 from changing quickly and prevents it from rising again after I reach my target. I figure that by going slowly I am removing large amounts of total PO4 from tank, rather than small amounts quickly which just get replenished through release from calcium carbonate surfaces.

I expect the OP forgot a zero next to the decimal in his readings.

100%, I goofed on my post and didn't put the 0 in the readings.. I can't seem to figure out how to edit the original post..

The test will read 0.07 one day, two days later, 0.12, then sometimes back to 0.05 -- it's all over the place within the same week.

I am using a BRS GFO reactor, light tumble on the media surface -- although it's not evenly distributed when it's tumbling..

I am using a Reefmat 1200, so no filter socks either (the other post mentioned changing socks)


Thank you for the replies and my apologies for mixing up the post.
 

Reef.

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Are you feeding reef roids or similar? You po4 seems extremely out of whack compared to your low nitrate, if not feeding coral food, my guess would be leaching out of your rock or your hanna checker is broken…could be high po4 but I would check those first.

With rowa its best to check the water coming out of the reactor, it should be zero then creep up, once it gets to near where your tank po4 is, then its time to change the rowa.

Remember too, as you remove po4, any the rocks and sand etc are holding on to will release into the water, unless they are exhausted of po4, giving the impression you are not fixing the problem…test po4 out of the reactor, keep up with changing the rowa on time and you will get there…if you are not using coral food.
 

Reef.

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100%, I goofed on my post and didn't put the 0 in the readings.. I can't seem to figure out how to edit the original post..
You can only edit your post for a short time after its been posted, if you pay for a membership of this site, you get to edit your posts indefinitely I believe.
 
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wintrmte

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Are you feeding reef roids or similar? You po4 seems extremely out of whack compared to your low nitrate, if not feeding coral food, my guess would be leaching out of your rock or your hanna checker is broken…could be high po4 but I would check those first.

With rowa its best to check the water coming out of the reactor, it should be zero then creep up, once it gets to near where your tank po4 is, then its time to change the rowa.

Remember too, as you remove po4, any the rocks and sand etc are holding on to will release into the water, unless they are exhausted of po4, giving the impression you are not fixing the problem…test po4 out of the reactor, keep up with changing the rowa on time and you will get there…if you are not using coral food.
Thank you! I never thought about testing the water out if the reactor to see if it is expired.

I do use RedSea AB+ once a week, but wasn’t sure if that was contributing. Great suggestions from everyone, I really appreciate all the responses!
 

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