[tom855]

So I just attempted to remineralize 5 gallons of RO water. I "was" pretty happy to measure:

TDS 133
GH 6
KH 3

This was with a new TDS meter, and new API test kits.

However, when I measured the pH of the same water (also with a new API test kit), I measured around 7.6. I realize there is some room for interpretation with liquid pH test kit, but there is no way (with repeated tests) that this is anything close to neutral.

Since I was measuring the water AFTER adding the minerals, shouldn't I be able to make a valid pH measurement? Shouldn't it have been much closer to 7.0?

What am i missing here? I'd really like to flood my new SpecV, but want to do it with water I know is correct. Help!

 

[Zoidburg]

More than KH effects the pH... and the pH may change even after you add the water into the tank.

Do you need neutral pH?

 

[Alphazygma]

I’m in a similar predicament, I’m trying to setup a tank for caridina shrimp, so I want my PH at 7 or slightly lower.
Even with 0 TDS water and then remineralize with Salty Shrimp gh+/kh+ it indeed goes over 7.

Reading around, this seems normal due to the KH added by Salty Shrimp.

Also, in reading around, to avoid raising the ph due to the kh , that the other recommended product to use instead is “Bee Shrimp gh+”

The downside for me, from what I read, is that KH is what helps avoid PH swings, a plus for shrimp, the downside, it raises PH which is not optimal for caridina.
And specially not optimal in a high tech tank with injected CO2, while paces, the PH could drop too fast were it not for the presence of KH, that is my understanding.

Still researching, so hopefully smarter people in this forum can pitch in with their knowledge.


Sent from my iPhone using Tapatalk

 

[crushalot]

You may want to read over the water chemistry threads some. Using KH and CO2 levels is a great way to estimate/figure PH generally: CO2 Chart
So you made new water at 3KH and based off the chart, assuming that it is probably in a jug or small container without aeration, the CO2 levels could be no more than 2.5 ppm (well aerated water can get to 3.0ppm of CO2) so the chart shows the exact PH it should be for a KH3 and 2.3ppm CO2 = PH 7.6.

If you want a (stable) lower PH you either need to lower your KH or add CO2. If you are not doing CO2 and want a lower PH, then using 1 - 2 KH is fine as it will buffer to keep PH stable in the 7.0 - 7.4 range, you don't need any more KH for buffering unless required by livestock.

I do this even with buffering substrates like Stratum or Aquasolum. You may need to fight the buffering of the substrate at first but within a week or so and water change or 2 and it should stay consistent.

 

[beanbag]

When I mix up SS GH/KH, I also got a pH a bit over 7. That's expected - the KH will push the pH up

 

[Dreya]

If you want to keep Caridina, use the SS GH only product, not the gh/kh. That will allow your ph to drop to below 7 which is what the taiwan bee/kong types need. And the buffering soils/alder cones also help to drop that down. You do not need much KH at all for bees. See care recommends below, applies to most of the caridina:

LINK REMOVED BY MODERATOR

It sounds to me like you might have the SS sulawesi mix? I never see PH over 7.1 (in the bucket) with the regular GH/KH mix. Or yeah, the drop test is just that inaccurate

I gave up on the drop PH tests as too vague and got an actual electronic PH meter ($70) from fisher scientific. This also means you need to buy the calibration standard solutions (4, 7,10 ph) to be sure it is functioning correctly. Get the hydroponics ones from amazon and save a bundle, dont buy the human clinical lab standards. Its a pain at first but the ease of use more than makes up for it imo.
I could not find my exact PH meter but this looks very close and even includes little sample vials of the cal solutions:

https://www.amazon.com/Apera-Instruments-AI209-Waterproof-Accuracy/dp/B01ENFOHN8/

https://www.amazon.com/gp/product/B017H73794/

 

[pucksr]

I've seen this before.
Rinse your test tube twice with tank water and shake it up. Then remeasure and let it set for 5 minutes.

If you still get a high pH, you have a problem. If this fixes it, then your problem was a false reading