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Testing parameters for EI

alto

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The reason your tank is a sewer is typically because you overfeed and do not do enough water changes. My high nitrate, high phosphate tanks are pristine.


While this is certainly true, it is a false assumption that simply having a high NO3/PO4 tank equates to the habitat contamination. There are many substances that contribute to contamination and those substances that are truly responsible for contamination, such as organic waste are easily controlled via water changes.

Cheers,

Bizarre responses, I'm guessing you didn't read for context :rolleyes:
 

alto

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you cannot really trust test kit readings and NO3 test kits are at the top of the list of poor value and inaccuracy. PO4 test kits are not far behind.
The kits use standard chemistry methodology that has "worked" in millions of laboratory tests, why should the chemistries immediately fail with aquarium water :confused:
- or is the inept practitioners? ;)

Sorry but I fail to see the logic in this paradigm
 

Delapool

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I thought the point of EI was that you dont need to test, you supply the ferts in abundance so they are never the source of a deficiency, no need to test. Save your money to buy some nice fish or something rather then test kits. During your initial cycle I can see he need to test, from there you should be able to start to rely on plant growth to see what is needed.

Good question - why test - extra money but extra time as well. Then even if you do test, is it useful?

For myself, I actually enjoy the testing and find it peaceful (so unlike work). Many people locally don't test using EI dosing and do well, I think that's fine. I don't care either way.

If I change the plant mass eg large pruning, this provides a check for me. If I see nitrates trend going up, I cut back on dosing and see nitrates trending down. So generally my test results match my expectations. If I didn't find test kits useful I wouldn't use them.

Generally I find kits precise as well. Threads where a test kit is not repeatable for same water have not been many I've seen but I find these the most worrying.

On the weekend, $72 bought 4 rams. Intention is to swap to discus but still planted at some stage. That cost is significant enough that the cost of kits in time and money is worth it, unless the accuracy is way off...
 

dw1305

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Hi all,
.....Generally I find kits precise as well. Threads where a test kit is not repeatable for same water have not been many I've seen but I find these the most worrying.

On the weekend, $72 bought 4 rams. Intention is to swap to discus but still planted at some stage. That cost is significant enough that the cost of kits in time and money is worth it, unless the accuracy is way off...
Nitrate tests
I know @alto is a scientist, and I would be quite happy that the NO3 levels he records are accurate, but I'm also convinced that there are problems with nitrate measurement, and that many people won't have followed, or fully under-stood the method (shaking with API kits, the need to acidify very hard water etc), and that their values will be much less accurate.

If you live in the UK you can get maximum, minimum and mean nitrate levels for your tap water from your water supplier, and by testing your tap water it should give you some idea of the accuracy of your test kit.

The main problem with colorimetric methods for nitrate measurement is that nearly all nitrate compounds are soluble, so you have to reduce the NO3 to NO2 before you can get a coloured insoluble nitrite compound that you can measure.

Conductivity and the Duckweed Index
I would approach this from a slightly different angle. If you want to keep soft water fish you can just use conductivity and the health and colour of a floating plant, as an indication of the <"nutrient status of your water">.

I don't think we will have any disagreement that a conductivity meter can give an accurate and reproducible values over a wide range of different water conditions (from DI water at less than 5 microS, up to seawater at ~53,000 microS).

A low range conductivity meter will be suitable for all freshwater aquariums.

Measurement of conductivity (TDS meters measure conductivity and then use a conversion factor (usually 0.64 to convert to ppm TDS)) doesn't tell you which ions are present, but you know that if you have a low conductivity reading that you don't have many of any ion.

I soft water fish and I just keep the plants growing, via the <"duckweed index">, and the conductivity level between 80 - 150 microS.

cheers Darrel
 

roadmaster

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Bizarre responses, I'm guessing you didn't read for context :rolleyes:

I understand that most of the nitrates,phosphates, that folk's fear, are due largely to the oxidization of the organic material that Clive mentioned (ie) Fish waste.fish food's.
These begin as Ammonia,then nitrites.and finally nitrates.
Is not so much the nitrate level's that hurt the fishes/invert's but how they arrived in the aquarium.
The oxidization of the organic matter first into ammonia and then nitrites is what harm's the fishes/invert's rather than the nitrate number from test kit.
the mineral salt's we add as fertilizer's are Inorganic and do not need to go through the oxidization and thus represent fare less of an issue.
Also as Clive pointed out, water changes on properly run tanks will never see Nitrate level's(if this is concern) that would be problematic even with addition of the dry mineral salt's we add as fertilzer's for you need many hundred's of ppm long term to see negative affect.
And these many ppm needed to cause possible harm,are way way,more than any popular dosing scheme call's for.
Is how the nitrates arrive that fish feel.. Ammonia,nitrites, from organic matter processed before they can experience nitrate issues.
 

Delapool

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Hi all,Nitrate tests
I know @alto is a scientist, and I would be quite happy that the NO3 levels he records are accurate, but I'm also convinced that there are problems with nitrate measurement, and that many people won't have followed, or fully under-stood the method (shaking with API kits, the need to acidify very hard water etc), and that their values will be much less accurate.

If you live in the UK you can get maximum, minimum and mean nitrate levels for your tap water from your water supplier, and by testing your tap water it should give you some idea of the accuracy of your test kit.

The main problem with colorimetric methods for nitrate measurement is that nearly all nitrate compounds are soluble, so you have to reduce the NO3 to NO2 before you can get a coloured insoluble nitrite compound that you can measure.

Conductivity and the Duckweed Index
I would approach this from a slightly different angle. If you want to keep soft water fish you can just use conductivity and the health and colour of a floating plant, as an indication of the <"nutrient status of your water">.

I don't think we will have any disagreement that a conductivity meter can give an accurate and reproducible values over a wide range of different water conditions (from DI water at less than 5 microS, up to seawater at ~53,000 microS).

A low range conductivity meter will be suitable for all freshwater aquariums.

Measurement of conductivity (TDS meters measure conductivity and then use a conversion factor (usually 0.64 to convert to ppm TDS)) doesn't tell you which ions are present, but you know that if you have a low conductivity reading that you don't have many of any ion.

I soft water fish and I just keep the plants growing, via the <"duckweed index">, and the conductivity level between 80 - 150 microS.

cheers Darrel

Nice idea.

Again though, I've seen new and old aquarium people quite successfully use these test kits. Let's say 0.1% of test kits are just plain totally wrong and 10% of people get stuck following the kit. Maybe it's 30%. And saltwater people will be more fussy on which test kits are useable for their needs.

By and large however, I simply do not see a large number of threads with test kit issues. I'd expect over the years (decades?), this should be a more active finding. There is no link I'm aware of that shows using test kits correlates to planted tank failure as more than statistical outliers.

I'm simply not seeing posted any reason to throw out any test kit (even if I bought a TDS meter which is on the wish list). If there is further reasoning or thread findings in another posted thread, I'd certainly be interested. Great discussion.
 

Delapool

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I understand that most of the nitrates,phosphates, that folk's fear, are due largely to the oxidization of the organic material that Clive mentioned (ie) Fish waste.fish food's.
These begin as Ammonia,then nitrites.and finally nitrates.
Is not so much the nitrate level's that hurt the fishes/invert's but how they arrived in the aquarium.
The oxidization of the organic matter first into ammonia and then nitrites is what harm's the fishes/invert's rather than the nitrate number from test kit.
the mineral salt's we add as fertilizer's are Inorganic and do not need to go through the oxidization and thus represent fare less of an issue.
Also as Clive pointed out, water changes on properly run tanks will never see Nitrate level's(if this is concern) that would be problematic even with addition of the dry mineral salt's we add as fertilzer's for you need many hundred's of ppm long term to see negative affect.
And these many ppm needed to cause possible harm,are way way,more than any popular dosing scheme call's for.
Is how the nitrates arrive that fish feel.. Ammonia,nitrites, from organic matter processed before they can experience nitrate issues.

Several hundred ppm of nitrate in either form I would find of note. I used to think it didn't matter - now not so convinced. Breeders here seem to have a heart attack if over 20ppm (test kit, not true). However thinking about it, this may include wild-caught cichlid fish. On the flip side I remember one tank going over 100ppm nitrates (test kit again) with no issues reported. Pretty interesting - was there any papers on this?
 

roadmaster

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Will never see Nitrate levels from suggested dosing schemes much over 30 ppm to be maintained .
Should never see much more in un planted fish only tanks if properly maintained, unless you are over stocking,over feeding,underfiltered,lapse maint,or all of the afore mentioned.
Could I suppose realize some nitrates from tap water supply but can easily reduce the amount's of nutrient KNO3 if this is the case.
Yes,there are scientific paper's out there that measured the affect's of nitrates in the hundreds of ppm on some sport fishes and a few of the ornamental fishes .
I expect they could be found fairly easily with some searching.
I was not an easy convert to adding the mineral salt's to my tanks so I spent some time searching/reading/experimenting for myself.
Would note that adding the mineral salt's can easily influence TDS so might be consideration for some wild caught species that come from water's with very low conductivity .
 

dw1305

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Hi all,
Breeders here seem to have a heart attack if over 20ppm (test kit, not true). However thinking about it, this may include wild-caught cichlid fish. On the flip side I remember one tank going over 100ppm nitrates (test kit again) with no issues reported.
The oxidization of the organic matter first into ammonia and then nitrites is what harm's the fishes/invert's rather than the nitrate number from test kit.
Unless you add a mineral salt like KNO3, the nitrate is the "smoking gun" of earlier high levels of toxic ammonia and nitrite, so it is difficult to tease out the cause of any long term sub-lethal effects.

It is also difficult to find toxicity levels for just NO3, problem is that it is only really aquascapers who add it to their tanks in significant amounts. There is this paper: <"Comparing the effects of high vs. low nitrate on the health, performance, and welfare of juvenile rainbow trout Oncorhynchus mykiss within water recirculating aquaculture systems">, where NaNO3 was added to the trout's water, that suggests that,
......study results provided strong evidence that relatively low NO3-N levels, 80–100 mg/L, were related to chronic health and welfare impacts to juvenile rainbow trout.........
Again though, I've seen new and old aquarium people quite successfully use these test kits. Let's say 0.1% of test kits are just plain totally wrong and 10% of people get stuck following the kit. Maybe it's 30%.
That is really the point, we don't know how many tests are accurate and how many inaccurate. Unless people have access to figures derived from appropriate analytical equipment how are they meant to know whether the figure they have got is accurate or not? That is the advantage of using the water companies figures, if your value lies out of their range, then something has probably gone wrong with your test kit.
If there is further reasoning or thread findings in another posted thread, I'd certainly be interested.
There has been quite a lot of discussion of this over the years, have a look at <"Testing for EI">, <"Accurate methods of measuring nitrate"> and <"Which NO3 Testing">.

cheers Darrel




 

zozo

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I resently found out that Nitrates in drinking water is related to methaemoglobinaemia (blue baby syndrome). This is the reason why water companies monitor it very closely. I do not know about other countries, but in EU regulations water companies should provide this information. In my country it is by default per region on their website and regularly updated. So parents of new borns can look it up on demand if it is safe to use tap water for their baby or not. It seams Uk has a simular treaty.
http://dwi.defra.gov.uk/consumers/advice-leaflets/nitrate.pdf

Wouldn't that be a beter starting point, to find out what your tap water nitrate level is? :) Than you have a pretty good accurate idea what you are putting in. I guess adding NO3 salts is pretty straight foreward to get to desired values if you need to up without the need of measuring.

I found out mine is < than 25 ppm from the tap, taking in account what the fish provide i was definitively wasting money on adding NO3.. I do not need it, get from the water company..
 

Delapool

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Our water supplies change by the season while the water company report is annual.

When these threads become formal, long-life stickies highlighting that hobby test kits result in failure of the following:

- cycling a tank,
- saltwater tanks,
- almost the first question with unhealthy fish,
- planted tanks,
- aquarium off-topic such as ponds and pools.

In short, just about every aspect of present tank-keeping -> then I will be beating down the door of the fish shop (actually the pool shop will be first). It would be a simple matter to start compiling thread statistics where use of test kits has resulted in failure. The chances are at least excellent for planted tanks. Thanks for the links, when there is a line of angry customers outside the shop, let me know.
 

roadmaster

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Depends on test kit being used, and who is doing the testing, as to how accurate result's are.(some folks can't / won't read/follow instructions.)
Brand new or ten year old test kits, may have different result's.
Test strips against reagent's being used might read different, or different brand test kit might read different ,and or some user error is common .
Most hobbyist grade test kit's can give ballpark values.
Water company report's are available any time here in U.S. with a phone call, and result's of weekly testing by Water company can be had for the asking.
Don't need to wait for annual report.
Many hobbyist test kit's used for measuring ammonia for example can read zero ,but actually,, there are always low levels of ammonia present. Too low for test to measure that is food for bacterial colony and plants as well.(created daily)
Fine line between what fauna can handle or can't.
 

dw1305

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Hi all,
Our water supplies change by the season while the water company report is annual.
Do you get maximum and minimum figures for the year?
When these threads become formal, long-life stickies highlighting that hobby test kits result in failure of the following:

- cycling a tank,
- saltwater tanks,
- almost the first question with unhealthy fish,
- planted tanks,
- aquarium off-topic such as ponds and pools.

In short, just about every aspect of present tank-keeping -> then I will be beating down the door of the fish shop (actually the pool shop will be first). It would be a simple matter to start compiling thread statistics where use of test kits has resulted in failure. The chances are at least excellent for planted tanks.
I'm not going down the route of the popularity of topics, if something <"is regarded as credible, it doesn't make it right">, but a search on Google would provide thousands of examples of failed cycling etc. This is <"aquarium, my cycle failed"> and this <"problems with nitrate test kits">.

In terms of what happens outside of fish keeping, in the aquaculture, waste and potable water supply industry they use a mixture of analytical methods and bioassay to quantify water, when scientists attempt to classify freshwater they use a mixture of analytical methods, BOD measurement and biotic index.

It isn't black and white scenario and that only one method can work, it is all shades of grey. You can cycle your tanks successfully with ammonia, and base your water management on the results of test kits, and plenty of people do, but I'm really interested in probability, not possibility.

I started all this because I was interested in simple robust techniques that every-one could use to increase their probability of being a successful fish keeper. Because I had experience of working on the bio-remediation of landfill leachate, I knew that you could use plant/microbe filtration and high levels of dissolved oxygen to improve the quality of grossly polluted water and I was pretty sure the same approach would work with less polluted water. When I started looking at aquarium literature I found that <"Diana Walstad and Horst & Kipper"> had already been down the same route.

After that I was expecting to be able use the testing methods, available to every-body, to successfully quantify their tank water. I have access to an analytical lab. (and the staff that work in it) so I could get pretty accurate figures for comparison. I believe that Tom Barr went down a similar route at <"UC Davis"> (see @xim's post).

cheers Darrel
 

zozo

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I looked at several UK water companies.. Indeed searching water quality with postcode didn't find one providing current nitrate levels only hardness and flouride. But do provide previous year Min/Max values and average. Most i looked at where all > 20 ppm during the whole year.. :)

One report from surrounding London area Affinity water company.
https://www.affinitywater.co.uk/docs/water-quality/TV023.pdf

But according DWI they should provide you with current data if asked.. And here is a list of all companies and phone numbers.
http://www.dwi.gov.uk/water-company-contact.htm

My country does provide current or latest nitrate test value on demand on their website. Probably not a international obligation.
But for UK it also only seems to be one phone call away to find it out. :)
 

dw1305

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Hi all,
But do provide previous year Min/Max values and average. Most i looked at where all > 20 ppm during the whole year.. :)
It depends a little bit where you are, most of the water in the S.E. and E. of England is pretty high in NO3, because it comes from a mixture of ground water, rivers and reservoirs and there is a lot of diffuse pollution from agriculture, sewage etc.

In the N. and W. of the UK the water tends to be much lower in nitrate.

I looked at our tap water today <"Postcode Result"> abstracted from a deep limestone aquifer, and about 7.5 ppm NO3 and 18dKH.

cheers Darrel
 
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zozo

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It depends a little bit where you are,

I can believe that.. UK is a pretty large country with a lot of water suppliers.. I only clicked a few to see.. All had over 20 ppm. Just meant to say, if i as not beeing Britain can find this out on the fly.. Than it must be peanuts for you.. :) You just did show that whit a simple poscode result.. :thumbup: What more accurate estimate reading can you get or need and for free. Next to what your plants tell you than you at least you know what you weekly put in with a water change. Or am i so far off?? After all it is Estimate Index!?
 

Delapool

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Hi all, Do you get maximum and minimum figures for the year? I'm not going down the route of the popularity of topics, if something <"is regarded as credible, it doesn't make it right">, but a search on Google would provide thousands of examples of failed cycling etc. This is <"aquarium, my cycle failed"> and this <"problems with nitrate test kits">.

In terms of what happens outside of fish keeping, in the aquaculture, waste and potable water supply industry they use a mixture of analytical methods and bioassay to quantify water, when scientists attempt to classify freshwater they use a mixture of analytical methods, BOD measurement and biotic index.

It isn't black and white scenario and that only one method can work, it is all shades of grey. You can cycle your tanks successfully with ammonia, and base your water management on the results of test kits, and plenty of people do, but I'm really interested in probability, not possibility.

I started all this because I was interested in simple robust techniques that every-one could use to increase their probability of being a successful fish keeper. Because I had experience of working on the bio-remediation of landfill leachate, I knew that you could use plant/microbe filtration and high levels of dissolved oxygen to improve the quality of grossly polluted water and I was pretty sure the same approach would work with less polluted water. When I started looking at aquarium literature I found that <"Diana Walstad and Horst & Kipper"> had already been down the same route.

After that I was expecting to be able use the testing methods, available to every-body, to successfully quantify their tank water. I have access to an analytical lab. (and the staff that work in it) so I could get pretty accurate figures for comparison. I believe that Tom Barr went down a similar route at <"UC Davis"> (see @xim's post).

cheers Darrel

Excellent does not equal possible or probable. I will settle on possible, not probable or excellent.

People cycle their tanks through ammonia, nitrite and nitrate (along with ph changes), using these hobby style test-kits. That's about as complex as it gets for a test kit to be useably accurate, precise and monitor trends. Tap water or distilled water can be tested in comparison. They did so using these style of test kits long before this thread, and they will being do so long after this thread. So over the decades, should a cycling tank be owned > don't do it with a test kit, I'd suggest that isn't tried with expensive fish. A convincing counter-argument is awaited with interest.

Sometime again over the decades - own a pool > don't test it over summer. Don't own a test kit. (Just in case, that's theoretically - I can't in all fairness suggest that practically). For anyone that has never owned a pool, these don't come with hand-held XRF devices along with a set of standards either and yet a functioning pool will be demanded.
 

dw1305

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Hi all,
People cycle their tanks through ammonia, nitrite and nitrate (along with ph changes), using these hobby style test-kits. That's about as complex as it gets for a test kit to be useably accurate, precise and monitor trends.........]They did so using these style of test kits long before this thread, and they will being do so long after this thread.
We aren't going to agree on everything, but it is true, people will carry on cycling with added ammonia and monitoring their water to tell when the tank is "cycled". It isn't an approach I'd recommend, but it isn't a guarantee of failure either.
Tap water or distilled water can be tested in comparison.
OK this is closer to the problems with testing for monovalent ions.

If you add a known amount of NO3 to DI water (using KNO3 etc. as your source), you will find that all testing methods (assuming you follow the correct procedure) will give you accurate and repeatable results. You can use serial dilution to create a standard curve and to ensure that your standards are on the right scale for the test kit method.

The problem is that you can't use assume that the same standard curve will work for water with other ions present (like tap or tank water), that may have have interference from other ions (like chlorine Cl-) or may be highly alkaline etc.

You can construct a standard curve by adding the KNO3 to your tank water sample, and then following the same procedure of serial dilutions. You don't know how much NO3 was in your water sample, but you now know how much you have added.

After you've drawn the new standard curve, you can derive the equation that will allow you to estimate the NO3 content of the tank water. This works (and is the approach I'd take), but I'm not sure that most people would consider it necessary.

If you want an example of interference from other compounds you can look at ammonia testing, where the presence of a water conditioner like Amquel or <"Prime"> will give you a positive ammonia reading, whether free ammonia is present or not.
So over the decades, should a cycling tank be owned > don't do it with a test kit, I'd suggest that isn't tried with expensive fish. A convincing counter-argument is awaited with interest.
You just need oxygen, plants and time.

You don't need the test kit, you can plant the tank fairly heavily, add some floating plants and wait until the plants are in active growth. Once the plants are in active growth, the tank is then fish safe and will remain so.

There is mention of sensitive fish in <"Do I need to cycle...">.

cheers Darrel
 

Delapool

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Hmmm, you had me at standards and then I got side-tracked. I'd love to repeat that old society meeting thread where various test kits (and members!) were put through their paces. It's an African cichlid society here though so chances are about nil (planted tanks I sometimes feel are viewed as an amusing novelty and eventually my 4ft will be converted to something more "productive").

I'll shoot across a pm as off-topic. In a nutshell though, I like the idea of standards and that rang a bell that the seachem nitrate test includes a reference test for 10ppm. I like seachem but I've always viewed that with suspicion (so can't suggest it). I'd expect the 10ppm reference test will show ~10ppm but that tells me nothing about say 40ppm readings and if really suspicious, the idea of putting out both kit and reference is just wrong (I'd have a reference test of a random reading inserted by a another company). I'd prefer a standard with commercial sign-off (appreciate your post though as it's really great), I'd like to investigate accuracy further and first up I need to trust the standard (eg are my ferts really pure KNO3 here). At some stage I'd like to submit water samples to labs used in the past (to check hobby-farm drinking bore water nitrate levels as mentioned above re babies so I'm hopefully confident on their testing).

For example, these are recent readings below. First three are solution tests; JBL is a strip test (yes, I know) which is read by iphone (not that easy it turns out). So first assumption is test kits are working on tank water and then yes, these are within 20ppm but within that band I'm suspecting that API reads relatively low and JBL reads relatively high. (I'm not suggesting anyone needs this accuracy and I don't care if people test or not, this is my own project thus off-topic). I'll shoot across a PM on standards.

API - 5ppm (expires 2019).
API - 5ppm (expires 2021).
CheMETs - 15ppm (second ampoule as first failed).
JBL ProScan - 18ppm (downlight shadows still tricky - second reading).

http://www.seachem.com/downloads/instructions/0960-Nitrate-4.4.pdf

https://www.chemetrics.com/index.php?route=product/product&product_id=120
https://www.chemetrics.com/index.php?route=product/product/download&file=pdf/nitrate_cadmium.pdf
 

dw1305

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Hi all,
It's an African cichlid society here though so chances are about nil (planted tanks I sometimes feel are viewed as an amusing novelty and eventually my 4ft will be converted to something more "productive").
I keep some cichlids (but not Rift lakes ones), and from posting on Cichlid forums I understand that there is a certain resistance to plants as the answer, and that threads that start off quite civilly can rapidly descend into a flaming war.
I'll shoot across a pm as off-topic. In a nutshell though, I like the idea of standards and that rang a bell that the seachem nitrate test includes a reference test for 10ppm.
That would at least tell you that the reagents are still good. The 10ppm NO3 solution will definitely be right (unless it has evaporated), because all NO3 compounds are soluble.
(eg are my ferts really pure KNO3 here)
Can you buy KNO3 as a liquid feed? produced by a company like <"Yara">. If you can then it will be of high purity. I don't know about Australia, I know in Europe it can be difficult to get nitrate compounds due to their potential use as explosives.
I'll shoot across a PM on standards.
You can use one of the on-line calculators (like <"Rotala Butterfly">) to get values, or I can email you an excel spreadsheet.
API - 5ppm (expires 2019).
API - 5ppm (expires 2021).
CheMETs - 15ppm (second ampoule as first failed).
JBL ProScan - 18ppm (downlight shadows still tricky - second reading).
I wouldn't be too unhappy with these. You could try shaking the API reagents for a bit longer, and maybe try diluting your tank water sample with RO. You could try 50:50 RO:tank and 75:25 RO:tank and see what you get.

cheers Darrel
 
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