Ph. 1-14 Test Paper Extensive Test Paper Litmus Test Paper Sonkir pH Test Strips，Test pH for Saliva Urine Water Soil Testing(2-Pack pH Test Strips)

These Ph. 1-14 Test Paper Extensive Test Paper Litmus Test Paper Sonkir pH Test Strips work great and are very easy to use. This was a good purchase.

One should understand what this is, it's purpose, and limitations before buying it. What you are specifically using it for makes a big difference on whether you will find it useful or problematic. [Kinda like don't buy a hammer when you actually need a saw.] Litmus paper comes in a variety of ranges and sensitivities, and you either have something with a wide range or something extremely detailed, but not both. This one uses a very broad scale litmus, running the entire range from 1-14. As such, if you need a high degree of detail, like to be able to differentiate between 7.8 and 8.0, this is not going to give you that level of detail and be worthless. But those detailed litmus papers also aren't going to give you that range that this one does either, and are probably limited to a range of 6.5-9.0 at most, also making it useless outside that range. There are no decimal values in this litmus reading and you'll not notice any significant difference between 4.0 and 4.5 for example. Also be aware that like all litmus, the texture of the paper is different than it is on the scale, thus giving it a slightly different look. What you're looking for here is pigment value, not an exact match in look. The same thing holds true in pH testing methods that use a liquid like phenolphalein or pH indicator such that you'd find in a swimming pool test kit. Essentially, this litmus would be completely inappropriate to use where a range of <1.0 where the result is mission critical. Again, it's designed for wide range, not high detail. But it makes it very appropriate to use in processes like cold or hot process soap making to know that you've got a finished product within an acceptable pH range like between 9-10, but where wrong calculations could leave you with highly alkaline soap. It's also completely inappropriate to use this to test human saliva or other bodily fluids that generally have a healthy range of about a half to a full point. This is close to that normal range that the litmus is calibrated to, it won't change much if at all, and it won't give you the detail that most people are looking for. This litmus will develop it's finished color within a second or two, making it a very fast paper. However, it should be noted for those not familiar with such testing, that this can only test a wet product, not a dry one. So for instance if testing a bar of soap, wet the soap with pH neutral water like distilled water, then wet the litmus paper with the resulting liquid/lather. I haven't seen how long the litmus will show a valid test, but you can make an accurate determination within a few seconds, and I've seen no change in the color, even 5 minutes out. Do NOT reuse litmus paper under any circumstance, though if in a pinch, using the other end that wasn't previously used might be acceptable.

Great product but the papers are stuck together and at fist extraction you would never know that there are 4 pieces stuck together. My guess is that the papers are cut out in bunches but they are not easily separated and have to be pried apart with a tool. Also, the yellow paper color rubs off on your hands - even before the paper gets wet.

Accurate, at least as far as I can tell, water tests at 7pH which is what it should be. Lemon juice tested at 4 which is low but every lemon will be different. My only complaint is the alkaline colors don't closely match the colors printed inside the cover. For example, testing one cleaner the main part of the strip is similar to 10 but the darkest part of the strip is close to 11 so which is it? But I remember the strips we used in college having the same problem so I won't hold it against these. You get 2 booklets of litmus strips in a small plastic ziplock bag, probably a lifetime supply for me. I use them to test the pH of various household cleaners to help me make homemade cleaning solutions and what I discovered is most are alkaline, even citric degreaser. Of course then you go around testing anything and everything from spit, coffee, OJ, milk, etc. Here are some of my results: Acids • Barkeeper's Friend, 2 • Citric acid + water, 1TB/Cup, 2 • Kaboom, 3 • Star San, 5 Neutral • Pine Sol Alkaline • HDX Citrus Degreaser, 10 (generic version of Zep) • Mr Clean, 10 • Scrubbing bubbles, 10-11 • Windex, 11 • Oxyclean, 12 Hot sauce, 4 Lemon juice, 4

unlike other reviewers here, i found a wide range of results depending on what i tested. not sure how "accurate" these really are, as i have no way to calibrate them, but i do get the same reading on similar things over time and have gotten readings as high as 10 and as low as 3. they are about the thickness of construction paper. very useful and great price. doesn't work on dark liquids.

Honestly I am not sure if it should be a 1 star or 5 star review. First off I bought these because one of my favorite internet canners uses them and I trust her. My issue is the date stamped on them. 2-22-21. They came with no literature explaining if that is a use by or manufactured date. Do they have a shelf life? If someone could let me know then I will change it to a 1 or 5 depending on the answer. I have not used them yet, do not know if I can trust them to be accurate. They are definitely inexpensive enough and a bargain if that date means nothing.

I had to update my review. I thought I was getting accurate readings and that there was a separate issue with my plants. Then I got a digital pH tester to ensure I was doing things right. After calibrating the digital tester, I tested my liquid feed with both the digital and these pH test strips. The digital meter consistently gave me the same reading on two different solutions that I mixed exactly the same: 5.6. The color the paper strips tested at could have been read as anywhere from 7-9 pH. That is a HUGE difference for cannabis plants and other things. My plants immediately began improving once I was pH'ing correctly. The writing in this package is mostly Chinese, the translation of the instructions are not correct, and the color on the strip changes immediately after pulling it out of the water making it hard to know what to read at. I've used different pH strips (with all English writing) that worked much better than this. My advice: get a made in America pack or spend the extra bucks and get a digital tester. Bottom line...don't get this one!

I use these for quick PH check ups, using my more elaborate PH meter is a bit of a ordeal compared to the paper strip method for quick checks on my hydroponic tanks. I use the meter when setting up the tanks for accurate PH measurements but requires 15 minutes to prep the meter, of the paper strips show my PH is way off I will then break out the meter. Found these strips to be accurate when compared to my meter readings. Good value based on the amount of strips received in the package.