PH discrepancy

[Sunny]

Hi everyone, after having my first guppies die on me, I’m trying to figure out my water. I’m showing a pretty big difference between the Coop strips and API test kit. The test kit did expire in January, but even before then it was showing my PH to be much higher than the aquarium coop test strips do (the difference didn’t matter until I tried to keep guppies!)

Thanks!

[CT_]

I have the same issue. it always reads under 7 for me. 

 

I found a reproducible condition and Corey had the lab test it. it worked in their lab so I think some of them have bad pH pads. 

[Sunny]

Oh, interesting. Do you know if the more  recent test strips have the issue resolved? 

[Patrick_G]

On 10/17/2021 at 11:03 AM, CT_ said:

I have the same issue. it always reads under 7 for me. 

 

I found a reproducible condition and Corey had the lab test it. it worked in their lab so I think some of them have bad pH pads. 

Mine read a bit lower than the API liquid test also, but based on the conditions of our Mystery Snail shells I’m inclined to trust the strips, or at least average the two readings. 

[Sunny]

I kind of believe the strips, too, based on how the guppy situation went, but I feel like there’s a huge difference between 6.8 and 7.8.

ETA: my water out of the tap is soft, which may also explain the guppy crash, which is why I’m not sure if it was ph or not?

Edited October 18, 2021 by Sunny

[Ken]

What two numbers do you see and how much of an impact would the difference make to the fish?

[Sunny]

I’m seeing 6.8 on the strips and 7.8 on the liquid kit, and I could be totally off trying to read the colors. It’s my understanding that 6.8 is barely acceptable for most fish and too low for live bearers, while 7.8 is a great number for most fish including live bearers. Right?

[CT_]

My water is low to mid 8s and the strips that I have always say under 7.  I validated my pH with a calibrated lab meter.

[Patrick_G]

On 10/17/2021 at 6:32 PM, Sunny said:

I’m seeing 6.8 on the strips and 7.8 on the liquid kit, and I could be totally off trying to read the colors. It’s my understanding that 6.8 is barely acceptable for most fish and too low for live bearers, while 7.8 is a great number for most fish including live bearers. Right?

I think 6.8 is actually very good for lots of aquarium fish including most Amazon species. Amazon Tetras, Rams, Angels, Corys etc. I’m not sure it’s it’s the best for livebearers but in my area we have soft, often slightly acidic water and there are lots of thriving livebearers. Many aquarists in the area use crushed coral or other methods to raise hardness and stabilize PH as much as possible. 
Someone please jump and correct me if I’m way off base! 

[Ken]

On 10/17/2021 at 7:32 PM, Sunny said:

I’m seeing 6.8 on the strips and 7.8 on the liquid kit, and I could be totally off trying to read the colors. It’s my understanding that 6.8 is barely acceptable for most fish and too low for live bearers, while 7.8 is a great number for most fish including live bearers. Right?

In my opinion, either of those numbers are fine. I don't think I would try to mess with the water parameters until they got more than .5 either way of them (who am I kidding, I wouldn't then). Your hardness and buffer look like you are good to go at that Ph to me. Like always if someone knows better I hope they chime in.

[Sunny]

Crushed coral has kept my ph from crashing but it’s never made it go up. But the two guppies I got just did horrible and I’d like to figure out what about my water is disagreeing with them before I potentially kill some more.

[Ken Burke]

I think this might eventually turn into one of those classic questions. Strips or liquid, Ford or Chevy, coke or Pepsi.  
 

For me, the liquid might be more accurate, but so many ways to go wrong.  gotta shake the bottle enough, hold the bottle straight up and down, count out the drops and wait long enough without waiting too long.  Then compare colors, and the vial is always between two colors.  I’ve heard sticking your tongue out the left side of your mouth helps, but I can’t tell for sure.

Strips are my go to solution.  So much easier.  And hey!  We are looking for significant change anyhow.

 

course, I’m not in my “right” mind  

 

 

[Ken]

On 10/17/2021 at 8:18 PM, Ken Burke said:

We are looking for significant change anyhow.

That.

[CT_]

At least for me, my defective ones don't register hardly any difference between ph 6 and 8.  While extreme accuracy isn't important here, we also don't want to be measuring time with a stopped clock.

But for me this is a "clock" that I don't really need so I didn't bother returning the strips.  After seeing corey's test I'm pretty confident that my next batch of strips will be okay.