Frustration with test kits differing results

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Yarkii

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I'd love to hear which test kits everyone is using, and particularly if anyone knows of a test kit that isn't as subjective as the ones I've got.

I started with the API 5 in 1 Test Strips when I just had a little 2nd hand goldfish tank. It measures NO3, NO2, pH, KH & GH.

I then bought the API Freshwater Master Test Kit (pH, High Range pH, Ammonia, Nitrite & Nitrate), and the API GH & KH Test Kit.

I also bought the Seachem Alert Combo for pH & Ammonia. They sit on suction caps inside the sump.

I started cycling a new 220L tank seven days ago. I'm using aragonite & coral sand as substrate, to raise the GH & pH as I have extremely soft water but want to keep livebearers.

For the first two days I only used the Test Strip for pH, KH & GH. The pH sat at 7.0 (it was always 6-6.5 in the goldfish tank). On Day 3 I started using the API Master Test Kit, and was surprised to see the pH shoot up to between 8.0 & 8.2.

Perplexed, I tried using a Test Strip as well, and it showed the pH as 7.0. That's a big difference.

There was an anomaly with the GH readings as well: 5 drops = 89.5ppm using the Master Kit, but 180ppm or more using the Test Strip.

By Day 4 I started using a measuring syringe to fill the test tubes, and realised that I might not have had a full 5mL in the Day 3 tests. The pH using the Master Kit read as 7.8, which was better than the previous day's reading. I didn't use a test strip as I'm almost out of them, but instead read the Seachem alert, which read 7.4 for the pH. GH was 8 drops = 143.2 (I find the decimal place rather amusing, when this is all so very inaccurate.)

On Day 5 I only tested ammonia & nitrite, using the API Master Test Kit.

On Day 7 (today), according to the API Master Test Kit, the pH is 8.0, or maybe more, and the GH was 8 drops = 143.2. According to the API Test Strip, the pH is 7.5, and the GH is 120+. According to the Seachem alert, the pH is 7.4. So that's three different pH readings with three different tests, and two different GH readings with two different tests.

With Ammonia, I've only got the API Master Test Kit & the Seachem Alert. On Day 1, when I added the calculated amount of ammonia to reach 3ppm, the API test kit read between 2 & 4, so I was happy with that. By Day 3 it read as 1ppm. By Day 4 it read as between 0.5 & 1ppm. But - by Day 4 I had the Seachem Alert in there, and it measures 0.05ppm, rather than 0.5ppm. Aaargh!!!!

Today the Ammonia reads between 0.25 & 0.5ppm (closer to 0.5ppm) on the API Master Test Kit, but still shows as 0.05ppm on the Seachem Alert.

Could it be that I've got a bad batch of tests in the Master Test Kit? Or that one or both of the other test types are faulty?

Nitrite readings (now that I have them) seem more closely aligned between tests: 2.0ppm+ on the API Master Test Kit and 3.0 on the API Test Strip.

The inconsistency between tests is driving me bonkers. Is there a test that doesn't rely so heavily on getting the water measurement precise (I'll have to purchase a better water measurement device I guess), the lighting in the room & subjective interpretation of colour similarities and differences? I just want to know what the water parameters really are.

TIA
:)

Sent from my SM-G900I using Tapatalk
 
I'm using aragonite & coral sand as substrate, to raise the GH & pH

For soft water that should give you a ph of 7.0 or very close to it. the carbonates in the coral and aragonite devolve in acidic water and push the PH up to 7.0. Carbonates do not resolve in water when the PH is above 7 and therefore will not push it up to 8.

I use tetra 6 in 1 test strips and they show my ph staying around 7. Sometimes I get really good plant growth which can push PH up to 8 but as soon soon after the lights go off it comes right down. For a time I had Hanna PH meter and it and my strips and meter were always in agreement. Currently MY PH meter is not working. I need to replace its sensor.

For ammonia I use a Hanna ammonia checker:
http://hannainst.com/hi700-ammonia-...N1nV3EkqoxJzNrfAeZsrUFnuunaYIVg4lfhoCB6nw_wcB

Its a little pricy but the accuracy is very good. I also have a alkalinity and Phosphate checker and all are easy to use and the accuracy and resolution are far better than any typical aquarium test kit. My alkalinity meter did fail shortly after I purchased it. I called them and they quickly sent me a new one with more reagent and more test vials.

Sadly they don't sell a nitrate meter and the nitrite meter is strictly low range. I would really like to see them sell a sulfate, hardness, and potassium checker. Unfortunately they only offer those in their desktop units which run about $1000.

Sorry I didn't see your post earlier.
 
It's super frustrating trying to find the accurate numbers.
I went thru this as well.

I use the tetra 6 in 1 strips to test GH and KH but don't rely too heavily on the PH from this as it always reads lower than what it actually is.

I like my API master kit for PH (which is always much higher than the tetra strip tells me).
I also like my API for Nitrate, Nitrite and Ammonia. I find them to be easier to read (although I get zero readings on all three of those from both kits.

Do not use syringes to gather the water (even though it makes life much easier than messing with the damn tubes in the tank.
You want to actually get the freshly rinsed (with tap water) tube down in the middle of the tank water and swish around and pick up then pour out until you're at the line of measurement....this is where you're truest reading will come from (I learned that here after getting all different readings and not understanding why).

When I water test my kitchen looks like a science laboratory.
 
Thank you so much, Steven & Jen. I really appreciate you both taking the time to help me out here. :)

Carbonates do not resolve in water when the PH is above 7 and therefore will not push it up to 8.

I'll try to attach a photo of the API Freshwater Master Kit High pH test from just before 1pm today (before the lights came on. It looks like 8.0 to me, but I really do seem to struggle with deciding how the colours line up. Does it look like 8.0 to you? (I've noticed that with photos, whether I use the flash or not can also totally change the look of the exact same test.)


I use tetra 6 in 1 test strips and they show my ph staying around 7.
I use the tetra 6 in 1 strips to test GH and KH but don't rely too heavily on the PH from this as it always reads lower than what it actually is.

Thank you. I'll try to find the Tetra 6 in 1 strips.

For ammonia I use a Hanna ammonia checker:

That looks fantastic! I am going to try to see whether I can purchase the Hanna ammonia checker and the pH checker too in Australia. If not I will look for another brand, I guess. For around $50, I think it might take away quite a bit of the frustration I am experiencing. I assume there will still be a lot of care needed to make sure the amount of water is as accurate as possible, and the drop sizes are as uniform as possible? Do you find that the reagants etc are of a similar cost to the test tube type testing scenario, and do you think it takes more or less or a similar time to conduct these tests compared to using test tubes?

You want to actually get the freshly rinsed (with tap water) tube down in the middle of the tank water and swish around and pick up then pour out until you're at the line of measurement....this is where you're truest reading will come from

Ah. For the first few tests I was testing water from the sump, but then I switched to taking it from the very top of the tank. Trying to get the level right without the syringe was driving me bonkers. Please tell me it's something that you get better at with time?

Maybe I could shove two hands in and take in 5mL with the syringe from the middle of the tank.....
 

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Not sure why the photo uploaded twice. It's the same photo.
 
Just a further question about the ammonia checker, Steven:


Hanna do have an Australian website (yay!). I notice that there's the low-range ammonia checker (0-3.0ppm, resolution 0.01ppm), and for a little bit more there's the mid range ammonia checker (0-9.99ppm, resolution 0.01ppm). Is there no need for measuring above 3.0ppm, or is it worth getting the medium for a little bit more?
 
Today the Ammonia reads between 0.25 & 0.5ppm (closer to 0.5ppm) on the API Master Test Kit, but still shows as 0.05ppm on the Seachem Alert.

The API ammonia test, tests both ammonia and ammonium while the The Seachem device detects free ammonia.

So the 0.05ppm reading on the Seachem Alert would be free ammonia.
 
The API ammonia test, tests both ammonia and ammonium while the The Seachem device detects free ammonia.

So the 0.05ppm reading on the Seachem Alert would be free ammonia.

Oh! I had not idea. Thank you so much! I think I'll just pay attention to the words on it instead ("Safe", "Alert" "Alarm", "Toxic"). :)
 
Please tell me it's something that you get better at with time?
It definitely is. I'm sure I didn't do it right for quite a while...
AND it's really important you follow the steps to the T! Like when it says to shake vigorously for a full minute (or whatever it says) make sure and do exactly that or your reading will be off!

Oh and when I read the color charts I make sure to do it with daylight behind me.
So...I stand with my back to the sliding glass doors in the kitchen and hold the vile up to the color chart with the vile against pure white!
This also makes ALL the difference!!! If I check it like this and then take it into my bathroom and check in that light...different results yet again.

Maybe I could shove two hands in and take in 5mL with the syringe from the middle of the tank
LOL I suppose you can! But all of these extra steps are just further ways to jack up your results.
You want middle tank water directly in the vile to get the most accurate reading.

I know....huge pain in the rear!!!
 
AND it's really important you follow the steps to the T! Like when it says to shake vigorously for a full minute (or whatever it says) make sure and do exactly that or your reading will be off!
Noted! Thank you. :)

Oh and when I read the color charts I make sure to do it with daylight behind me.

I think the fact that I've been doing a lot of the tests late at night is going against me.

So...I stand with my back to the sliding glass doors in the kitchen and hold the vile up to the color chart with the vile against pure white!
This also makes ALL the difference!!! If I check it like this and then take it into my bathroom and check in that light...different results yet again.
Yeah - I've noticed that if I take a photo with the flash then straight away again without the flash, the reading will jump up to the next colour step. I've started taking a flash photo every time.



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I notice that there's the low-range ammonia checker (0-3.0ppm, resolution 0.01ppm), and for a little bit more there's the mid range ammonia checker (0-9.99ppm, resolution 0.01ppm). Is there no need for measuring above 3.0ppm, or is it worth getting the medium for a little bit more?

If you have 1ppm ammonia in your tank you should do a water change. So for ammonia getting a reading range of 0-10ppm doesn't tell you anything different other than the water is really bad. However the Low range checker when you get below 0.5 the lower reading scale allows you to make a judgment call on if you need to do anything. normally in my tank the reading is zero (0.00ppm). However there have been a few times i have read like 0.03ppm. That is a safe reading (don't need to do water change) but in that case I do count my fish and shrimp and look for reasons for it. (it could mean something has died. One time when I did get such a low reason I found one of my nitrite snails had died.

So in my opinion for these devices I generally prefer having the capability to read lower than i need rather then higher than i need. Having the ability to read lower is generally more useful to me. I have not had a problem with counting the drops of reagent and I do use a string to accurately put in 10ml. Test only takes a minute to set up. When I am done i rinse both vials with ro water and then store them full or RO. This prevents stains from appearing on the vial. Do accidentally leave a vile full of reagent. That may permanently stain the glass.

When ordering one verify you are getting the range you need not one with a range you don't need. Also keep in mind they do have a few salt water meters. Those won't work for fresh water.

Hanna doesn't sell a PH "checker". The PH probes they sell work very differently than liquid test kits. It is electronic device you stick in the water and after a couple of minutes it gives you a reading. These probes need to be periodically calibrated with 1 or 2 PH calibration solutions, You also need a storage solution and a cleaning solution. If you don't use these solutions it may not read correctly, may fail prematurely, or never read accurately. I ended up spending about the same amount of money on all of these solutions as I did on the probe which came with only a small amount of calibration or storage solution. This is what I purchased:
http://hannainst.com/hi98100-checker-plus-ph-tester.html

You can get cheeper ones but the instructions can be hard to understand (made i china), and don't read accurately even with calibration. I purchased in the past one of these cheap chines devices and it was basically worthless. and based on reviews may treat them as disposable.

Despite all that my PH probe died after one year.(I count celibate it and it took longer and longer to generate a stable reading. I can order a new sensor but is it worth it? i haven't decided. A PH checker using liquid chemicals would be nice and wouldn't need calibration and storage solutions. But they don't make one.
 
If you have 1ppm ammonia in your tank you should do a water change. So for ammonia getting a reading range of 0-10ppm doesn't tell you anything different other than the water is really bad. However the Low range checker when you get below 0.5 the lower reading scale allows you to make a judgment call on if you need to do anything. normally in my tank the reading is zero (0.00ppm). However there have been a few times i have read like 0.03ppm. That is a safe reading (don't need to do water change) but in that case I do count my fish and shrimp and look for reasons for it. (it could mean something has died. One time when I did get such a low reason I found one of my nitrite snails had died.

So in my opinion for these devices I generally prefer having the capability to read lower than i need rather then higher than i need. Having the ability to read lower is generally more useful to me. I have not had a problem with counting the drops of reagent and I do use a string to accurately put in 10ml. Test only takes a minute to set up. When I am done i rinse both vials with ro water and then store them full or RO. This prevents stains from appearing on the vial. Do accidentally leave a vile full of reagent. That may permanently stain the glass.

When ordering one verify you are getting the range you need not one with a range you don't need. Also keep in mind they do have a few salt water meters. Those won't work for fresh water.

Hanna doesn't sell a PH "checker". The PH probes they sell work very differently than liquid test kits. It is electronic device you stick in the water and after a couple of minutes it gives you a reading. These probes need to be periodically calibrated with 1 or 2 PH calibration solutions, You also need a storage solution and a cleaning solution. If you don't use these solutions it may not read correctly, may fail prematurely, or never read accurately. I ended up spending about the same amount of money on all of these solutions as I did on the probe which came with only a small amount of calibration or storage solution. This is what I purchased:
http://hannainst.com/hi98100-checker-plus-ph-tester.html

You can get cheeper ones but the instructions can be hard to understand (made i china), and don't read accurately even with calibration. I purchased in the past one of these cheap chines devices and it was basically worthless. and based on reviews may treat them as disposable.

Despite all that my PH probe died after one year.(I count celibate it and it took longer and longer to generate a stable reading. I can order a new sensor but is it worth it? i haven't decided. A PH checker using liquid chemicals would be nice and wouldn't need calibration and storage solutions. But they don't make one.

Thank you so much, Steven. I really appreciate the detail and explanation you provide. :)

I did see that pH probe on the Australian Hanna site, and noticed the cleaning & storage solutions. I think I'm going to invest in both this and the low range ammonia checker. Thank you so much!

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