Yep, they summed it up. Also, check out,
Ph Fluxuation? How to control?.
If you are using the wide range pH liquid tester, then you might get a more distinguishing color if you use low range pH liquid tester or a high range pH liquid tester. I think the API master freshwater test kit has both of these liquid testers. The low range liquid pH tester only tests within a range of 5.0~7.7 pH, best I can recall off hand. The high range liquid pH tester only tests within a range of 7.7~10, best I can recall off hand. So, you
might get a more precise color when using the appropriate high or low range tester. The wide range pH tester is particularly helpful when trying to figure if to use the high or low range pH tester.
A digital pen instrument, such as the Martini, will test down to a measurement accuracy of +/-
.05.
The liquid pH test kits have a measurement accuracy of +/-
.2, that is assuming you are good at matching colors.
Test strip pH test kits have a measurement accuracy that is anybody's best guess, but I think it might be reasonable to assume near an accuracy of +/-
.2.
Do not confuse resolution accuracy with measurement accuracy.
The liquid pH test kits are fine, but, if you are not comfortable with its accuracy, then a good pH digital pen instrument will generally cost more than $50. However, even with the digitial instruments, accuracy is never an infallible variable. It ultimately depends on the application and why you need to know a higher accuracy.
For the longest time I used the
Milwaukee Martini pH 56, but now I use a different device. Here is the
meter and it's replaceable electrode on amazon. These need to be properly stored if you want the readings to be accurate. None of these devices are gauranteed to never fail; so, if your readings are off, then be sure to call the manufacturer and they most often will switch out the diodes for free if it is within warranty. It is the electrode and diode that is important. The problem with the cheap pH meters is that there are no replaceable diodes and so you can not garauntee the quality of the device; this is meaning, when something goes wrong, then the entire device must be tossed and purchased again. Generally, the diodes is the most expensive component in these pH meters due to they all vary in durability, quality, and accuracy of results.
The problem with finding good digital equipment is that everyone will give competing opinions!! So, do your best to sift through all of the nonesense to make a good decision. I have had good luck with the Martini pH 56, but there have been others that have not had good luck with them.
The diode is the component that is the brains of these devices. If the diode is starting too fail, then the rest of the device becomes quite irrelevant. Proper storage ensure the diodes are hydrated and keeps its accuracy.
So, properly storing the diode is quite important. Do
not use distilled water. Here's a good example of the usual storage instructions:
How to Store, Clean, and Recondition pH Electrodes. Every manufacturer has a special storage solution to be used with their meters. All of these solutions have some concentration of potassium chloride in them and this causes the solution to evaporate rather quick, when this happens chloride salt crystals are formed. No worries. Simply just stir the diodes in some
luke warm water to dissolve and release the crystals. Be very careful to not scratch the diodes.
If you want to skip the intricate cleaning instructures, which do yield better results when compared to the manufacturer recommendation, then you can simply just use the manufacturer recommended storage solution.
On the Martini, I actually screwed off the diod, wrapped the microchip connector end in plastic, with a piece of paper towel in it, and secured it with a very tight rubberband then filled a small tupperware container, with lid, to seal it tight and stored it in my refrigerator on the very bottom shelf. Be sure it does not tip over since you do not want the microchip connector to get wet.
The Maritini device is known as a pH pen instrument. If you want even better accuracy, down to +/-
.01, then you will need to look into continuous monitoring instruments. These instruments are very much more expensive than the pen instruments, but the diode used is of extremely high quality and very durable. The best continuous monitoring instrument's retail cost above $400 due to the quality of the diodes. I use the
Hanna BL 981411 pH Mini Controller, that uses
cabled flow-thru electrodes, enclosed in a
NEMA weatherproof enclosure. If you can find these devices already sold in a bundle, then this would be the cheaper route. Individually buying the pieces is more expensive due to tax and shipping costs.
If your situation is unique or you want to talk options, then give
Hanna Instruments a call. They were very help to me, but do not get discouraged if someone is not available so leave a voicemail and they will return your phone call.
Good luck to ya. I hope this was of any help to ya!! :cheerful: :claphands:
