Phosphate Battle

fixel2002

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Hi all,

My Fluval 13.5 Evo is about 3 months now and everything has been doing really well up until a few days ago, I came home from work to my torch and goniopora both closed. I didn't bother testing anything because it was due for its weekly 10% water change, so I went ahead and did it, tested afterwards.

Everything was looking good, Nitrates were a little low at 7.23ppm, I added some NeoNitro to get it up to 10ppm.
Phophates on the other hand were at .90ppm, after water change, and I had put a new bag of Chemipure elite in the day before.

Is this high enough to make my corals close? And how should I go about getting the Phosphate lowered? I read that you don't want to drop them drastically too soon and that it should be done overtime, so I guess I shouldn't do a large water change? Should I ditch the Chemipure Elite and just get some GFO?

Any advice is appreciated, TYIA!
 

bluemon

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I wouldn’t say .90 is high enough to cause any trouble.

I keep mine there with higher nitrates and everything thrives.

Did you test for other things?

Alkalinity, calcium, magnesium, etc…
 

DarkReefer

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I wouldn’t say .90 is high enough to cause any trouble.

I keep mine there with higher nitrates and everything thrives.

Did you test for other things?

Alkalinity, calcium, magnesium, etc…

Do you mean 0.09?
I would've thought 0.9 would be considered pretty high? Especially when the often reccomended number is around the 0.04 ?
I know people have seen a lot of success anywhere between the 0.09 -0.1 range though.
 

bluemon

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Do you mean 0.09?
I would've thought 0.9 would be considered pretty high? Especially when the often reccomended number is around the 0.04 ?
I know people have seen a lot of success anywhere between the 0.09 -0.1 range though.
No I mean 0.9.

I’ve kept mine between 0.5 and 1 before

All corals were doing well, no algae problems.

I only started seeing problems at 2.5+

Edit: that being said, it’s a very mature tank that can take higher nutrients.

But I would measure the other skeleton building parameters first to rule out any other problems
 

JonoH

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Did you test right after the water change?

I was always under the impression you should wait a day or so after a WC - not sure why though!

0.9 is pretty high, but them being closed up is probably from the lower nitrates. My torches open and close depending on the time of day and what is being dosed at any given time.
 

rishma

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Hi all,

My Fluval 13.5 Evo is about 3 months now and everything has been doing really well up until a few days ago, I came home from work to my torch and goniopora both closed. I didn't bother testing anything because it was due for its weekly 10% water change, so I went ahead and did it, tested afterwards.

Everything was looking good, Nitrates were a little low at 7.23ppm, I added some NeoNitro to get it up to 10ppm.
Phophates on the other hand were at .90ppm, after water change, and I had put a new bag of Chemipure elite in the day before.

Is this high enough to make my corals close? And how should I go about getting the Phosphate lowered? I read that you don't want to drop them drastically too soon and that it should be done overtime, so I guess I shouldn't do a large water change? Should I ditch the Chemipure Elite and just get some GFO?

Any advice is appreciated, TYIA!
Agree better high than low.

On its own, I would not say 0.9 high enough to stress the corals but fast changes can stress them. I would say 0.9 is on the high side but many tanks don’t for well when people aggressively lower phosphates.

Small tanks are tough to lower them because products like GFO (chemipure elite) remove phosphates so fast you end up stressing the corals. Then phosphate bounces back to the original level because phosphates are bound to the rock and sand and release back to the water when the phosphate level in the water is lowered. That cycle adds additional stress.

Water changes will not effectively lower phosphates for same reason. There is a huge reservoir of phosphate now bound to the rock and sand that will replenish the water when you replace it.

Consider what you are feeding and how much. Reef Roids is a huge source of phosphate, for example. Consider reducing feeding if phosphate continues to increase.

If you really want to lower phosphates….do it very very slowly. Chemipure elite has GFO in it so monitor phosphates frequent when you are using it. I don’t know how much GFO is in it but suspect it’s more than I would use on a tiny water volume.
 

DarkReefer

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No I mean 0.9.

I’ve kept mine between 0.5 and 1 before

All corals were doing well, no algae problems.

I only started seeing problems at 2.5+

Edit: that being said, it’s a very mature tank that can take higher nutrients.

But I would measure the other skeleton building parameters first to rule out any other problems
That's interesting, I didn't realise that was still an alright number. I guess if you've got a mature tank as you say, anything could be possible.
 
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fixel2002

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Hi all,

My Fluval 13.5 Evo is about 3 months now and everything has been doing really well up until a few days ago, I came home from work to my torch and goniopora both closed. I didn't bother testing anything because it was due for its weekly 10% water change, so I went ahead and did it, tested afterwards.

Everything was looking good, Nitrates were a little low at 7.23ppm, I added some NeoNitro to get it up to 10ppm.
Phophates on the other hand were at .90ppm, after water change, and I had put a new bag of Chemipure elite in the day before.

Is this high enough to make my corals close? And how should I go about getting the Phosphate lowered? I read that you don't want to drop them drastically too soon and that it should be done overtime, so I guess I shouldn't do a large water change? Should I ditch the Chemipure Elite and just get some GFO?

Any advice is appreciated, TYIA!
Agree better high than low.

On its own, I would not say 0.9 high enough to stress the corals but fast changes can stress them. I would say 0.9 is on the high side but many tanks don’t for well when people aggressively lower phosphates.

Small tanks are tough to lower them because products like GFO (chemipure elite) remove phosphates so fast you end up stressing the corals. Then phosphate bounces back to the original level because phosphates are bound to the rock and sand and release back to the water when the phosphate level in the water is lowered. That cycle adds additional stress.

Water changes will not effectively lower phosphates for same reason. There is a huge reservoir of phosphate now bound to the rock and sand that will replenish the water when you replace it.

Consider what you are feeding and how much. Reef Roids is a huge source of phosphate, for example. Consider reducing feeding if phosphate continues to increase.

If you really want to lower phosphates….do it very very slowly. Chemipure elite has GFO in it so monitor phosphates frequent when you are using it. I don’t know how much GFO is in it but suspect it’s more than I would use on a tiny water volume.
Reef roids may be the culprit, I had been going heavier on them on purpose to increase nitrates, before I got the NeoNitro. Guess that wasn’t a good idea lol.
 

JonoH

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Reef roids may be the culprit, I had been going heavier on them on purpose to increase nitrates, before I got the NeoNitro. Guess that wasn’t a good idea lol.
Yep, that'll do it!

Reef roids jacks phosphates not so much nitrates!
 
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fixel2002

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I wouldn’t say .90 is high enough to cause any trouble.

I keep mine there with higher nitrates and everything thrives.

Did you test for other things?

Alkalinity, calcium, magnesium, etc…
Yeah, right after water change my alkalinity was 8, I dosed to increase it to 9.4dkh.

Cant remember the calcium and magnesium readings, but both were good.
 

CHSUB

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I have no clue what this means😭

I’ve never watched the Matrix, that was before my time, pardon my ignorance.
Aside from your reefing inexperience with adding no3, the Matrix Movies are a must watch….it will change your life and imo, based on “reality”!

I’m surprised also that The Matrix is not required in schools today, they don’t teach “reality” I guess?
 

bluemon

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Yeah, right after water change my alkalinity was 8, I dosed to increase it to 9.4dkh.

Cant remember the calcium and magnesium readings, but both were good.

This is a bit concerning.

You make it sound like you dosed in the tank to raise the alk from 8 to 9.4 in a short amount of time.

1. What was the Alk before the change?
2. How rapidly did the alk change from 8 to 9.4?
 
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fixel2002

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Alk should’ve been close to 9.4 prior to change. I dosed it all at once, BRS calculator says not to increase it more than 1.4dkh so I figured it’s safe.
 

BryanM

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.9 is definitely high, but there are plenty of tanks that have thrived with nutrients that are abnormally high.

I would definitely stop the roids, and start looking to lower phos slowly, but I would not panic.
 

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