Weird PH liquid test readings

Recently I've been struggling to read the results on my PH tests.
I have the Aquacare Pro test strips and the API Freshwater Master Test Kit.
I've always followed the instructions exactly. I've been getting different readings on the liquid Vs strip tests, but as they are me guessing which colour is closest, this could be my own human error.

Today it's clear that either there is a fault in my kit or I'm reading/testing it wrong lol
With the PH test I'm reading 7.6 or above, and on the high range PH test I'm reading 7.4 or below.

Any ideas?

Attached are images of the liquid tests (high range and normal) and the water parameters I've been tracking since I started the tank 12 days ago.

PS. I assume the fluctuations in PH are due to the seiryu stone in my hardscape.

PPS. Is it better to hold the test tube against the white area of the test kit colour guide or hold it slightly in front of it? The colour darkens due to shadow when the test tube is touching the paper.

rebe said:

With the PH test I'm reading 7.6 or above, and on the high range PH test I'm reading 7.4 or below.

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I've had same issue with the API liquid tests as well with pH and high pH, is a pain. Not sure on solution. I love all the API liquid test kits apart from the pH one. Maybe we just have to have an approx. So you know you have a pH of over 7 and probably under 8

AlexT said:

I've had same issue with the API liquid tests as well with pH and high pH, is a pain. Not sure on solution. I love all the API liquid test kits apart from the pH one. Maybe we just have to have an approx. So you know you have a pH of over 7 and probably under 8

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Thanks! Shame if that's a common problem

I use the liquid test kit and my tests have always seemed fine.

That blue colour in your picture doesn’t really match the card but it could be the picture

In the instructions it does say if the PH is lower than 7.4 and you use the High PH regent it will always show the colour that corresponds to 7.4

Same goes with the Low Range test

The photo of the high range test shows the lowest colour, so that's either 7.4 or lower than 7.4 - the tester can't measure lower than 7.4 so it'll show that colour however low it is.

The lower range tester is trickier as the photo shows the test chart with different shades from mine - the colours on the chart are much stronger than my chart and bluer. But the tube doesn't march any colour on my chart, though that could well be my laptop screen. If the colour of the water is blue, that's the highest colour on the lower range tester which means 7.6 or higher.
That's like my pH, the highest colour on the low range tester and the lowest colour on the high range tester. I call that pH 7.5.

As essjay npoted, you will get different pH readings from the high range and normal range liquid test kits. You first need to ascertain which test to use, and that depends entirely on the pH of the source water. You obviously cannot test this with the kits, so you can usually obtain the pH value from the water authority if you are on municipal water (check their website, or call them). Or you can use a pH calibrator apparatus (if I have the correct name), which some aquarists use. It is expensive, but it will give you an accurate result. You have to out-gas the CO2 if testing yourself, at least I assume this can affect the test with this apparatus too.

Once you know the source water pH, then the test to use is the one that includes this number. Always use this test, the other will not be accurate.

You can also get a ’Wide range” pH test. Nutrafin has one. It covers from quite low - 4.5 I think, to 9 all in one test so it may give you a more consistent result.

Thank you everyone for your advice and insights! I actually ordered wide range test strips a few days ago, so that should hopefully clarify what the ph actually is :]

Still not sure what my PH is exactly.
The tap water seems to be 6.5-6.75 (according to ECENCE test strips) and my tank water seems to settle somewhere between 7 to 8?
I think the PH rise is from the seiryu stone in my hardscape. THe ECENCE strip reads 7.25 - 7.5 whereas the AquaCare (orange one) seems lighter than 7.2 or 7.6.
At this point I don't know what to do. There are cheap digital PH readers on amazon, but the reviews for those are really mixed. The PH tests in the API Freshwater Master Test Kit aren't helpful either.

I just want to know the PH of my tank water, but I feel like I'm going around in circles trying to nail it down!
Does anyone have any ideas?

Would the PH fluctuation after a water change upset future fish?

Is the QT tank full of water now? That might be one way of finding out if the seiryu stone in the main set up is raising the pH, because you would have a "control" if that's the right term with the QT tank. I know me and you have both had the same issue with the API pH liquid tests, but they are probably good enough for what we need to know. The key thing for you would be to find out if there is going to be a difference between tap pH and tank pH, either way, at least you are not experiencing any extreme pH ranges.

You are right about not wanting to subject the set up to swings of pH at water changes. One of the more experienced in pH impact (on fish) on the forum could advise better.

Having spent a lot of time reading on this forum than doing other things that need doing in my life lately, I am firmly of the opinion that just sticking to the API liquid tests are the best way forward, because lots of others also use them which means that when there is issues we can all relate or have some problem-solving suggestions.

As you are becoming a water parameter nerd like many of us, have you got the tests for GH and KH? There is a good saying that we keep water and the water keeps the fish, so I think the obsession with water parameter is actually good! And best of all, it's good for the fish!!!

rebe said:

Still not sure what my PH is exactly.
The tap water seems to be 6.5-6.75 (according to ECENCE test strips) and my tank water seems to settle somewhere between 7 to 8?
I think the PH rise is from the seiryu stone in my hardscape. THe ECENCE strip reads 7.25 - 7.5 whereas the AquaCare (orange one) seems lighter than 7.2 or 7.6.
At this point I don't know what to do. There are cheap digital PH readers on amazon, but the reviews for those are really mixed. The PH tests in the API Freshwater Master Test Kit aren't helpful either.

I just want to know the PH of my tank water, but I feel like I'm going around in circles trying to nail it down!
Does anyone have any ideas?

Would the PH fluctuation after a water change upset future fish?

Click to expand...

First quetion, when testing tap water pH are you remembering to out-gas the CO2? The level of dissolved CO2 in tap water can be surprisingly high, which is not in itself bad, but you have to out=gas it by letting a glass of water sit 24 hours, or brisly agitating it to drive out the CO2. The resulting pH test should then be closer to what the pH actually is. This might explain the difference of 7 to 8 for example.

Second, you have soft water so in the aquarium the organics will lower the pH over time. This can vary, but it is another possible factor affecting the pH testing. BTW, you do not have to outgas CO2 in aquarium water, just fresh tap water. And this does not apply to other tests (GH, KH, ammonia, etc).

Byron said:

First quetion, when testing tap water pH are you remembering to out-gas the CO2? The level of dissolved CO2 in tap water can be surprisingly high, which is not in itself bad, but you have to out=gas it by letting a glass of water sit 24 hours, or brisly agitating it to drive out the CO2. The resulting pH test should then be closer to what the pH actually is. This might explain the difference of 7 to 8 for example.

Second, you have soft water so in the aquarium the organics will lower the pH over time. This can vary, but it is another possible factor affecting the pH testing. BTW, you do not have to outgas CO2 in aquarium water, just fresh tap water. And this does not apply to other tests (GH, KH, ammonia, etc).

Click to expand...

I had never even heard of out-gassing before! I assumed the difference I noticed after a water change was because of the seiryu stone, but this might not be the case at all, when I first put my tank together I was researching the hardscape. I might not have even been sold genuine seiryu stone so maybe its not anything.

• "Seiryu stone contains calcium carbonate, which can dramatically affect the aquarium water. Specifically, this rock causes the pH levels and water hardness to increase. Basically, using Seiryu stone generally results in alkaline, hard water."

^^ ( https://www.aquariadise.com/seiryu-...ly affect the,results in alkaline, hard water. )

• "Frequent water changes will help keep your PH/dKH from going too high but the more acidifier / acid buffer / CO2 you add to the tank the more of the stone will dissolve to counteract the buffer."

^^ ( https/www.plantedtank.net/threads/seiryu-stone-i-think-ive-made-a-big-mistake.1207834/ )