Shouldn't I be able to see Phosphate after dosing?

Jib

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I've been struggling to get my Phosphates up, and have been dosing NeoPhos to try and raise the levels. According to the Brightwell calculaiton on the bottle, I should only be dosing 1ml to achieve a .03 reading. My Phosphate is still at zero, so have been gradually increasing my dose daily and I'm up to 5 ml, with still no results. According to the calc on the bottle, 5ml should result in a .15 reading.

My routine is test the levels, then dose, then check again at the same time the next day. Out of curiosity, I tested again after 2 hours. I would think I would get a reading after this short amount of time. Still zero. Would you expect to Phosphate show up on a test 2 hours after dosing?

I'm using a Salifert test kit which I verified is accurate (mixed a measure amount of NeoPhos in a measured amount of fresh saltwater and test kit returned expected results).

Thank you,

Jib
 

Cory

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I've been struggling to get my Phosphates up, and have been dosing NeoPhos to try and raise the levels. According to the Brightwell calculaiton on the bottle, I should only be dosing 1ml to achieve a .03 reading. My Phosphate is still at zero, so have been gradually increasing my dose daily and I'm up to 5 ml, with still no results. According to the calc on the bottle, 5ml should result in a .15 reading.

My routine is test the levels, then dose, then check again at the same time the next day. Out of curiosity, I tested again after 2 hours. I would think I would get a reading after this short amount of time. Still zero. Would you expect to Phosphate show up on a test 2 hours after dosing?

I'm using a Salifert test kit which I verified is accurate (mixed a measure amount of NeoPhos in a measured amount of fresh saltwater and test kit returned expected results).

Thank you,

Jib
The usual answer is po4 is binding to calcium carbonate surfaces such as sand and rock.
 
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Jib

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The usual answer is po4 is binding to calcium carbonate surfaces such as sand and rock.

Yep. You need to dose until you get to an equalibrium.
Continue to go slow and test often as you are. Youll see results eventually.

So if PO4 is binding to the rock and sand, does it reach a "saturation" point, where it wouldn't bind moving forward?

Any thoughts on if I should continue to raise the dose or hold steady at something like 5ml? Just worried once I hit a point that 5ml might be an overdose. Although, I'm not sure .15 would drastically hurt anything. Only have 1 clownfish and a few Zoas.
 

vetteguy53081

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After dosing anything, allow 12-24 hours before testing allowing disbursement and likely accuracy.
 

Cory

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. 15ppm po4 wont hurt corals but may cause some algae growth. Its possible organisms use it as fast as you put it in and measure for it.
 

Flatlandreefer

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Just curious, how big is your tank?

It can take several days/weeks to get a consistent phos reading in my dosing experience.
 
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Jib

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Just curious, how big is your tank?

It can take several days/weeks to get a consistent phos reading in my dosing experience.

It's a 14G, but realistically only hold about 9ish of water. I dose based on the 9.

I've been dosing NeoNitro as well. N03 jumped almost immediately. Thats why the P04 has been so frustraing.
 

Flatlandreefer

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NO3 is easier to keep detectable than PO4 in my experience. Dose more or even do your current dose 2x day until it starts to creep up. As long as you test every day or so you should be ok. It will probably just take some time. Also more fish always helps.
 

Randy Holmes-Farley

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So if PO4 is binding to the rock and sand, does it reach a "saturation" point, where it wouldn't bind moving forward?

Any thoughts on if I should continue to raise the dose or hold steady at something like 5ml? Just worried once I hit a point that 5ml might be an overdose. Although, I'm not sure .15 would drastically hurt anything. Only have 1 clownfish and a few Zoas.

yes.

just keep dosing
 

ScottB

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I was well into my second liter of Phos before I was able to keep a reading.

If you had some stony corals I would be encouraging you to get measurable PO4 established before dosing any NO3. Nitrate are easy for them to extract from the water. They work much harder to consume PO4.
 

PatW

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As a caution, I believe that all systems are different. What is plenty in one system may not be good in another.

Lately, I have been running phosphates at 0 with the Hanna ULR phosphorous test (which I think it the most sensitive on the market with a low range of .0003. I test first thing in the morning and get 0. If I feed about 50% extra the day before, I will get a low phosphorous reading.

For corals, I have birds nests, acropora, montipora, euphylla, fa via, acan and a few others. They are all doing fine. I have tangs and they get nori and they POOP LAVISHLY.

So you might not need to worry too much about it.

When I test to confirm my dosing, I mix the dose in about 20 times RODI and dump it in. I have pretty high flow and I figure that things are well mixed in 15-30 minutes.
 

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