15-Pack pH Meter Buffer Solution Powder for Precise and Easy PH Calibration, PH Calibration Powder Solution 6.86,4.01,9.18

The instructions must be followed precisely. Even the temp of the test water makes a difference. If your distilled water is not at 77 degrees, you need to adjust for that. We found that even if the ph tester says it can adjust for water temp, it will probably not, at least the first time you calibrate it. It took us a couple of times to realize that we could not compromise even the smallest. If it says 750ml of test water, it means exactly that, 750ml, not alittle less or more. If you follow the instructions, these will work well for calibration of your meter.

These buffers are easy to use because the instructions are clear and the reference values are provided on the back of the sachet. A single sachet lasts me for half a month in refrigeration using small portions to calibrate my sensor controlled by a micro controller. Recommended for use with any type of pH sensor!

Sometimes cloudy looking and sometimes not? Was able to calibrate with it.

These work great for making standard pH testing solutions to calibrate your lab meters. For the money you cannot beat these. I have had great luck with using these to test and calibrate my pH meters in my lab. Don't forget to use ionized water.

These are packets of calibration medium that I need to recalibrate my meross ph meter. They arrived ahead of schedule and are exactly what I ordered and need for calibration. They should work exactly as those enclosed in my new ph meter for it's initial calibration as they are the same size and brand, so I'm ready for any needed recalibration.

Easy to use, need for ph pen calibration.

Not the most accurate but good for fish tanks & pant hydro if your pen uses the range. My biggest issues is the one you need the most the 6 is the least you get , which means you have to buy a lot of these . You can find other's @ a better cost savings

The product was very easy to use! The three ph buffer solutions that are sent are perfect for meters like this one that does a 3 point calibration! Plenty of packs left over to do another 4 calibrations when needed!