Sky high phosphates

VaughnH

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Ten ppm is high, but I wouldn't call it sky high. I doubt that the fish or plants would do anything different with that much phosphate. How do you know you have that much? If it is by testing, you need to calibrate the test kit before accepting that you really do have that much.
 

Tom Barr

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One thing to consider in such a test is that your number of replicates is only 1.

If we tested 20 Seachem test kits, and ran 20 test each over a wide range, then you'd have a good example of testing with supporting replication.

That's a lot of test kits and still does not mean that next year when they change or switch over to one reagent batch from another, that the kits are the same this time.
Nor over time the effectiveness/accuracy of the test kit as it ages.

So calibration is still the way to go, I just never trust something otherwise.
Lamotte had the best accuracy, we had 5 of them together at a club meeting and they all where dead on.

But that might have changed after 10 years :)

The test you did was great, you just needed 20X as much and 7x as many test runs per kit to get good stats. Of course that would cost a lot though:)

FYI, SeaChem and Lamotte use the same reagents for NO3.


Regards,
Tom Barr
 

Michael

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My test kit is the API. Results showed the max of 10ppm so it could be 100 for all I know. Regardless, all my fish are fine except my GBR's. The only problem I see is the Phosphates. When I don't add Phosphates in my fert rituals I get 1 - 2 ppm, when I add it goes off the charts. I stopped adding the Phosphates but was told by numerous knowlegable people that I was making a mistake. My tanks is 300g, not that that makes a difference. I want to keep my GBR's alive in this tank, I now have them in a 40g and they are spawning and doing great but I don't have the high phosphates in that tank, this seems to be the only difference.
 

aquabillpers

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Tom Barr;18762 said:
One thing to consider in such a test is that your number of replicates is only 1.

If we tested 20 Seachem test kits, and ran 20 test each over a wide range, then you'd have a good example of testing with supporting replication.

That's a lot of test kits and still does not mean that next year when they change or switch over to one reagent batch from another, that the kits are the same this time.
Nor over time the effectiveness/accuracy of the test kit as it ages.

So calibration is still the way to go, I just never trust something otherwise.
Lamotte had the best accuracy, we had 5 of them together at a club meeting and they all where dead on.

But that might have changed after 10 years :)

The test you did was great, you just needed 20X as much and 7x as many test runs per kit to get good stats. Of course that would cost a lot though:)

FYI, SeaChem and Lamotte use the same reagents for NO3.


Regards,
Tom Barr

Well.

Manufacturing companies with reputations to protect employ quality control methods to insure that what they ship meets their standards. Chemical manufacturers, like kit makers, check each batch and if there is a significant variation from standard, they dump it.

There is really no need to check 20 Seachem (or whoever's) kits. One can safely assume that they will be consistent with the standards of the manufacturer.

Calibration might be the way to go, but I don;t think that every user of test kits has to calib rate
 

aquabillpers

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Tom Barr;18762 said:
One thing to consider in such a test is that your number of replicates is only 1.

If we tested 20 Seachem test kits, and ran 20 test each over a wide range, then you'd have a good example of testing with supporting replication.

That's a lot of test kits and still does not mean that next year when they change or switch over to one reagent batch from another, that the kits are the same this time.
Nor over time the effectiveness/accuracy of the test kit as it ages.

So calibration is still the way to go, I just never trust something otherwise.
Lamotte had the best accuracy, we had 5 of them together at a club meeting and they all where dead on.

But that might have changed after 10 years :)

The test you did was great, you just needed 20X as much and 7x as many test runs per kit to get good stats. Of course that would cost a lot though:)

FYI, SeaChem and Lamotte use the same reagents for NO3.


Regards,
Tom Barr

Well.

Manufacturing companies with reputations to protect employ quality control methods to insure that what they ship meets their standards. Chemical manufacturers check each batch and if there is a significant variation from standard, they dump it.

There is really no need to check 20 Seachem (or whoever's) kits to get a reaonable idea of their accuracy. One can safely assume that they will be consistent with the standards of the manufacturer. Process manufacturing isn't like the biological sciences, where often one needs a number of separate of tests/specimens to reach a conclusion. Manufacturing is much more controllable than nature.

I don't think that it is reasonable to expect that every user of test kits will calibrate that kit each time that a replacement kit is purchased. What we need is "Consumer Reports" kind of place where tests of kits can be posted. I couldn't find one when I suspected the accuracy of my phosphate test kit, so I did my own and posted the result.

Bill
 

Tom Barr

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Even higher quality companies such as Hanna and others have poor batches time to time. Unless they test their batches often and routinely, there's little way to ensure the accuracy.

They generally do when customers complain, that's about it and simply refund or replace. Who knows if they do or not test their batches often?

If they did, they'd say so to add value and marketing to their line. I would if I made test kits. :idea:
It would be foolish business wise not to tell folks this if they did it.

Testing is a reference science and as such, you need to test the kit at least once and if it sits over time for long periods(6 or more months). Bio science or not, the no# of replicates is still the same, the issue is likelyhood, Bio, manufacturing etc does not matter.

I'm highly skeptical of my data and want to be able to justify the results if asked and to make sure I did not over look anything.

That is why I test after all:idea:
Not everyone is going to though.

We all know that.

To be sure, to be able to offer the methods that show the test kit protocol is accurate, not to rely on company promises or beliefs or assumptions, I do things that way.

I think offering a test comparison like yours is great, but as you say, more needs to done there.

We did a similar test in the club about 10 years ago and have used mostly Hach and Lamotte ever since.

I've gone to lab spects the last 4 years which I calibrate every time I run test.
I generally will freeze the test samples and thaw for testing all at once as it's much faster to do test that way.

I will test 20 samples at a time and know they are all accurately measured.
Even our scales are calibrated by us for weights.

How far does a hobby need to go?
Well, a little calibration is good for most interested in narrow control for NO3 and PO4.

General wide ranges, Seachem is a decent company and I know Greg well enough and have discussed the issue with him several times over the years.
They are the only company that gives you a ref NO3 solution also:D

As far as PO4, it's non toxic to aquatic life, 100ppm ought not to have any adverse effect on any critter.



Regards,
Tom Barr













Is the PO4 at 10ppm toxic? It's non toxic even at 100ppm, to every aquatic form of life I know of. I've not seen any studies on toxicity because...well, it's non toxic for the most part over a very high range.
 

Michael

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Tom Barr;18782 said:
As far as PO4, it's non toxic to aquatic life, 100ppm ought not to have any adverse effect on any critter.



Regards,
Tom Barr


Is the PO4 at 10ppm toxic? It's non toxic even at 100ppm, to every aquatic form of life I know of. I've not seen any studies on toxicity because...well, it's non toxic for the most part over a very high range.

Okay, with that said, what would be the effect of high levels of PO4 in a planted tank?
 

Tom Barr

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Not much, once you hit 2-3ppm, not much is gained or shown.
It's not bad in other words.

But you do not need that much and hitting a target at 2-3ppm is not hard either.
Simply reducing the PO4 dosing and a water change or two ought to mitigate, that all of course as I've stated, depends entirely............on whether the test kit is actually accurate or not.

I belabor that point and have for well over 10 years now..........
Long before I became I went to school to become a nerd:p

Regards,
Tom Barr