Is there something wrong with my API test kit? Or aquarium water?

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Brickosaurus

Jack Dempsey
MFK Member
Dec 11, 2022
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So something is wrong here regarding my pH. And idk if it's my master kit, or my tank water.

I made a previous post about this but there is some more details that complicate things.

Let me explain...

I just finished cycling my new 29g community tank. Like I siad in my previous post, I was hoping to have 8 to 10 neons, 1 to 2 honey gouramis, 3 platys, and a bristlenose pleco.

I recently purchased an api freshwater master test kit off of Amazon and tested my water. All the other tests came out fine except mt pH, which was very dark blue. So I used the high range pH and that came out as a light pink (with a mix of orange?)

That color isn't exactly on the chart, so I tested my tap (which is from a well) and it read at 7.4 which should be perfectly fine for the fish I was wanting. I tested my tank water again, thinking that I must have done something wrong. Nope! The tank water still showed up pink!

So I tested my goldfish tank for pH and that showed up as pink as well! I did a large water change with both tanks and it was still pink.

I assumed that maybe the pH from my tap raised over time, and that my tanks were not the problem. So I put my tap water in a tube and let it sit out overnight and nothing changed. The tap was still 7.4.

I tested the tank water again, and it was still pink. And it didn't match anything on the chart! Regular pH test was still dark blue.

When I did this test it was late at night and I fell asleep before I could empty and rinse the tubes.

When I wake up I find that the tank water went from pink to 7.4! Now I'm entirely confused, and very stressed.

It can't be anything in my tank, because my goldfish tank gets the same result. I decided get the tank water tested at two LFS's and both of the stores said that the pH was around 7.8 to 8.0

Since both stores confirmed that it was around 8.0 I went ahead and got a 3 platys, and a bristlenose. Because they would do fine in water that hard.

I'm still so confused. I forgot to take the tap water to get tested, which I should have done.

But is the test kit faulty? I asked API about this problem over the phone, but they didn't have any immediate answers and they told me to email instead, I emailed and it's been a day and still no response.

I'm still very confused. And I have so many questions.

Like why is the tap at 7.4 pH and not the tank?

Why is it reading 7.4 even after I let the tap sit for overnight?

And why does the tank water change from pink to 7.4 after a day?

Why is my goldfish tank reading as pink as well?

And why is the tank water around 8.0 when it was tested at the pet store, but my tap is 7.4?


Here is a pic for reference. One on left is the tap, and on the right is the tank water. This is what they both look like 15min after testing
16722762405365011453329351003594.jpg

And even if the test kit is faulty that still means my pH is high.

I keep seeing MANY conflicting thoughts on whether a high pH is safe for most community fish.

Some people say that you can put fish like tetras and gouramis in 8.0 pH if you get fish from local stores And that they have kept these fish in this kind of pH for years and had no problems, that the fish are happy and healthy. And what really matters is keeping the pH consistent.

And on the other hand you have people who say that you have to keep fish as nature intended. And that the fish won't be happy and healthy in that water that isn't like their natural habitat.

Also I've seen some sources that say honey gouramis will do fine in higher pH. Is this true?

Any help or info about this situation would be helpful. Thanks!
 
How long are you waiting after you add the pH test solution and inverted the test tube a couple times to mix it up before you read the test results? You should be reading the results immediately. The longer the solution sits, the more the reading will change.

On your other post I suggested putting a sample of your well water in a clean glass container and letting it rest for 24 hours rather than using the test tube to hold the sample. You want as much air to act on your water sample to allow any off gassing of carbon dioxide (CO2) especially if you have a deep well or your well water is very cold.
 
How long are you waiting after you add the pH test solution and inverted the test tube a couple times to mix it up before you read the test results? You should be reading the results immediately. The longer the solution sits, the more the reading will change.

On your other post I suggested putting a sample of your well water in a clean glass container and letting it rest for 24 hours rather than using the test tube to hold the sample. You want as much air to act on your water sample to allow any off gassing of carbon dioxide (CO2) especially if you have a deep well or your well water is very cold.

Yes, I inverted the test tube. And I did immediately check the results, I left it out longer accidentally.

Sorry I misunderstood you about the tube. I'll retry it the right way.

Do you think neons would be fine in 7.8 to 8.0 ph?
 
I've not kept any tetras except for the Black Skirt Tetra and they did fine in my 7.6 pH well water.

Did you ask your LFS what they keep their pH at for their fish? Some stores do keep certain species at different water parameters though it should be noted on the tank itself, at least my LFS does.
 
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I've not kept any tetras except for the Black Skirt Tetra and they did fine in my 7.6 pH well water.

Did you ask your LFS what they keep their pH at for their fish? Some stores do keep certain species at different water parameters though it should be noted on the tank itself, at least my LFS does.

I did not ask. I'll can them though and check
 
The most common reason your tank water would be higher PH is you have rocks or sand in the tank that contains limestone/shells etc.
 
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