Which Is More Accurate - Ph Test Strip Vs. Liquid Kit

[dsiegel13]

I was having a pH problem according to both my Jungle Labs test strips and my API test liquid, both had me dipping in the low 6.0's.

So, I add some Alkaline Booster, and test 20-25 mins later w/ both the strips and the liquid and I am getting completely different readings.

Strips pH = 6.8

Liquid pH = 7.6 (the H2O went from yellow to blue)

Which in most peoples experience is more accurate? I am new to testing pH for my tank, so I am trying both, but with the health and safety of my fish in mind I want to make sure that I am getting proper readings.

Please help.

Thanks.

 

[Hunterprey]

Liquid test kits

 

[Caprichoso]

I would think that if they are both quality test kits and not expired that they should both be accurate? I've used both and personally don't see the difference.

 

[ian]

the actual Ph test stips are accurate enough for what we need them for. In fact we use them at work to test urine Ph and Stomach acid Ph. They are easier to use than regant test kits as there are IMO there is more room for error with a liquid test kit for Ph.

 

[fishguy2727]

Liquid, no doubt about it. If you are using strips you may be mor eaccurate guessing.

Yes, they are used for major medical things, where the difference 1.0 or more, not 0.1 or 0.2. Don't waste money on strips.

 

[Bignose]

Liquid, no doubt about it. If you are using strips you may be mor eaccurate guessing.

Yes, they are used for major medical things, where the difference 1.0 or more, not 0.1 or 0.2. Don't waste money on strips.

But for fishkeeping, a difference of 0.1 or 0.2 pH units is basically meaningless. If a fish cannot handle a change in pH of 0.1 or 0.2 units, then it is in serious trouble.

Or to put it another way, there is no pH value for fish keeping where if a value of X is good, a value of X + 0.2 or X - 0.2 pH units is now bad. No fish is that sensitive. The pH swings in nature are more severe than 0.2 pH units, and the swings in our tanks are more severe than 0.2 pH units.

Lastly, any kit made for a hobby is going to have error margins of at least +-5% and probably closer to +-10%. Those error margins make trusting the pH reading to within 0.1 or 0.2 pH units pretty much meaningless -- which is fine because as above, we don't need that level of accuracy anyway.

So between the fact that knowing a pH to +- 0.2 pH units and the fact that our test kits don't measure that accurately anyway -- I'm not sure it really matters.

If the topic is just measuring pH and only measuring pH, then I think a strip that gives an answer within 1.0 pH units is good enough for fishkeeping.

Now, I will agree that the liquid test kits for ammonia and nitrite are better. And, coupled with that you can usually by a liquid kit with ammonia, nitrite, and pH tests all together, I think most serious hobbyists end up with liquid pH tests anyway. But, I don't think that liquid pH tests are a necessity.

 

[Bignose]

Strips pH = 6.8

Liquid pH = 7.6 (the H2O went from yellow to blue)

1) the actual pH of the water is probably between 8.0 and 6.4-ish. The difference of 0.8 pH units on your test is well within the error margins of both the liquid and the strip tests. Quite simply, no test mass produced for the fish keeping hobby have very tight error margins. They are manufactured cheaply as the margin when selling the kits are pretty thin, and then the human element also adds measurement error.

2) Most fish would be pretty happy in water between 8.0 and 6.4. Or, using the figure from the beginning of the post, most fish would be just happy in water with a pH in the low 6.0s, too.

So, the real question, in my mind, becomes: what fish are you trying to keep, and are you trying to do something special with them like breed? And, is the pH in the low 6.0s steady, or continuously dropping? And, do you know your KH or GH? If you have the value for KH that's preferable, but a value for GH can help make a decent guess about the KH.

 

[fishguy2727]

Again, if you are going to use strips just save some money and guess.

Use a good liquid kit.

Agreed, What fish are we talking about?

IME it is almost always better not to bother with pH at all. High quality food and water are all that is needed and messing with the pH in most situations is not needed or even beneficial, especially if you use products that just bring the pH up or down and don't actually buffer the water to a particular pH. This can cause the pH to go up and down every time you add that product, which is much worse than being at a stable 'unideal' pH. Stable, high quality water and high quality food and the fish should thrive.

 

[dsiegel13]

So, the real question, in my mind, becomes: what fish are you trying to keep, and are you trying to do something special with them like breed? And, is the pH in the low 6.0s steady, or continuously dropping? And, do you know your KH or GH? If you have the value for KH that's preferable, but a value for GH can help make a decent guess about the KH.

Agreed, What fish are we talking about?

I have Platties and Tiger Barbs in there. I am not opposed to the Platties breeding, cause that is what they do anyway. Everything I read about the Platties is that they like it a little more alkaline than normal, so trying to push the pH and Alkaline up to between 7.0-7.5.

My GH is a constant 75 and my KH was 80 as of last night, prior to that it was a constant 40 (at least according to the test strips that I use). I have dosed 3 times in the morning with Seachem Alkaline Regulator, with results... the pH am/pm was 6.0/6.8 on Tuesday, 6.6/7.0 on Wednesday, and 7.0/??? (will know tonight when I check) today. Think that should be good for what I was shooting for (this is all according to the liquid test kit as the test strips are wildly different)

Going to stop dosing over the holiday weekend, and hope that the pH settles in to the higher value. Have my weekly H2O change scheduled for Tuesday of next week, so then will see how that plays into things.

 

[fishguy2727]

Monitor all weekend, it can take some time to figure out exactly how the tank is going to run.

 

[Bignose]

Platies and Tiger Barbs are both some of the most hardy and adaptable fish. They will both be fine in a pH of the low 6.0s. I wouldn't try to change the pH for anything.

And, the common livebearers (guppies, mollies, platies) are such, er, prolific spawners that I have little doubt that they would spawn in a pH of the low 6.0s.

 

[fishguy2727]

If you want to increase pH/KH one of the best and safest ways is to add a bag of crushed coral to the filter, just like carbon (possibly replacing carbon). This provides a constant supply of KH (which controls/increases pH, to a point). This means it will be effective, stable, and constant.

 

[SchottayB]

I've used both. I trust the liquid more the strips seem to change each test