Huge drop in Nitrates very quickly?

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That’s getting concerningly low on phosphate, if accurate. I’d feed more or dose P.
Dropped back down to .018ppm. Can the rocks be depleting the phosphates?

Once I dose neophos is it almost instantly or do I need to wait a certain amount of time till it will show on a test?
 

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If phosphate is low and you try to dose it, rocks and sand will bind some and organisms will use some and the levels will be lower than you expected by dosing.

Phosphate dosing shows on a test kit as soon as it mixes in, but then binding to surfaces is also taking place over a period of minutes to hours to days.
 
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If phosphate is low and you try to dose it, rocks and sand will bind some and organisms will use some and the levels will be lower than you expected by dosing.

Phosphate dosing shows on a test kit as soon as it mixes in, but then binding to surfaces is also taking place over a period of minutes to hours to days.
Ok so that is definitely the case here. I have been dosing enough neophos to bring it up to 0.3ppm but the highest I've seen is 0.05ppm than later in the day drops back down to 0.02ppm ish.
 

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Ok so that is definitely the case here. I have been dosing enough neophos to bring it up to 0.3ppm but the highest I've seen is 0.05ppm than later in the day drops back down to 0.02ppm ish.

Yes, that’s normal. The reverse happens too, such as with water changes. Some phosphate desorbs from the rocks and raises it back toward where it started.
 

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Ok so that is definitely the case here. I have been dosing enough neophos to bring it up to 0.3ppm but the highest I've seen is 0.05ppm than later in the day drops back down to 0.02ppm ish.
Are you actually measuring 0.3 ppm after you add phosphate, allowing some time for mixing?
 
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Are you actually measuring 0.3 ppm after you add phosphate, allowing some time for mixing?
I'm dosing in amounts that should be raising 0.03ppm. The amount of times I've done so over the last 3-4 days should have brought it to 0.3ppm at least. It's depleting faster than I am adding i guessh
 

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I'm dosing in amounts that should be raising 0.03ppm. The amount of times I've done so over the last 3-4 days should have brought it to 0.3ppm at least. It's depleting faster than I am adding i guessh
Pretty normal. If/when my phosphate drops low I typically dose enough extra (in addition to my normal daily dose) to add 0.15ppm and keep doing that daily until I am able to hold around my target of 0.1.
 

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I'm dosing in amounts that should be raising 0.03ppm. The amount of times I've done so over the last 3-4 days should have brought it to 0.3ppm at least. It's depleting faster than I am adding i guessh
The point is that you are assuming the dose is correct. You need to actually measure it to confirm nothing went wrong.
 
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Pretty normal. If/when my phosphate drops low I typically dose enough extra (in addition to my normal daily dose) to add 0.15ppm and keep doing that daily until I am able to hold around my target of 0.1.
Ok I will give that a try. Thank you
 

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I am calculating the dose and precisely measuring with a syringe

I think Dan is allowing for math issues, imperfect product, volume estimate issues, etc.

In any case, though, it is normal to need way more than calculated. :)
 
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I think Dan is allowing for math issues, imperfect product, volume estimate issues, etc.

In any case, though, it is normal to need way more than calculated. :)
Ok I understand.

Yeah I'm definitely doing the calculation right. Neophos shows the formula on the bottle and it's very straightforward. Only other thing I can think of is my tests are off. However they don't expire till later this year
 

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Ok I understand.

Yeah I'm definitely doing the calculation right. Neophos shows the formula on the bottle and it's very straightforward. Only other thing I can think of is my tests are off. However they don't expire till later this year
Always a good practice to test after addition (allow for mixing) to confirm the dose is giving you what you want.
 

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