Most reliable, accurate ph pen?
- Thread starter Johnxnyg
- Start date
wyteberrywidow
Global
I was recommended the blue lab combo meter. Also i hear the bluelab guardian (i think thats the name) is another good and reliable one.
ShirkGoldbrick
Active Member
Ph pens are very sensitive pieces of equipment. If you don't take care of them they're not going to last regardless.
If you want the most bang for your buck and accuracy you need:
-two small glass cups
-two squirt bottles
-calibration solutions(likely 4 and 7)
First, calibrate by directions.
Now, fill up one cup enough to immerse the electrode in pH 4, and one cup for pH 7. Fill one squirt bottle with 4, one with 7.
Store the pen in the pH 7 solution, but before you put the pen in rinse it off into a separate "trash" jar with the pH 7 squirt bottle.
Once a week calibrate in the pH 7 cup, then rinse in trash jar with pH 4 solution and set in pH 4 cup and calibrate to pH 4. Use pH pen, then rinse with pH 7 squirt bottle into trash jar and put back into pH 7 cup until next use. Always rinse the pen before putting into either jar, you can check calibration every time you use it this way.
You will still have to change out your storage cups periodically due to evaporation and keep them topped off enough to immerse the electrode. Best to use a buffering pH calibration solution for this reason.
If the pen ever dries out you can ruin it very quickly.
If you want the most bang for your buck and accuracy you need:
-two small glass cups
-two squirt bottles
-calibration solutions(likely 4 and 7)
First, calibrate by directions.
Now, fill up one cup enough to immerse the electrode in pH 4, and one cup for pH 7. Fill one squirt bottle with 4, one with 7.
Store the pen in the pH 7 solution, but before you put the pen in rinse it off into a separate "trash" jar with the pH 7 squirt bottle.
Once a week calibrate in the pH 7 cup, then rinse in trash jar with pH 4 solution and set in pH 4 cup and calibrate to pH 4. Use pH pen, then rinse with pH 7 squirt bottle into trash jar and put back into pH 7 cup until next use. Always rinse the pen before putting into either jar, you can check calibration every time you use it this way.
You will still have to change out your storage cups periodically due to evaporation and keep them topped off enough to immerse the electrode. Best to use a buffering pH calibration solution for this reason.
If the pen ever dries out you can ruin it very quickly.
Yea i didnt realilze how sensitive it was and was stiring the mixture with it. I hit the sides a couple times im sure it messed it up. I have a blue lab on the way and I just spoke with hydrofarm about the Autopilot ph doser and he said they use the same meters as bluelab and there both solid... Gonna print out what you said shirk and give it a go... The calibration solution will come in the mail tomorrow...
Shrik im having trouble understanding what you are trying to say in your statment.
Store pen in PH 7 solution? Or Tap water? Or PH 4? Rinse it off before i use it with ph 7?
Shrik im having trouble understanding what you are trying to say in your statment.
Store pen in PH 7 solution? Or Tap water? Or PH 4? Rinse it off before i use it with ph 7?
ShirkGoldbrick
Active Member
Store it in pH 7 between uses. But don't just dip it in your res and put it in the cup of pH 7 directly, you'll change the pH of the solution by doing that.
You use a little squirt bottle and over a separate jar or trash can or something you rinse the electrode and wet area off with a squirt bottle of the pH 7 solution so that the pen doesn't affect the solution.
Ditto when you calibrate. Don't just calibrate to 7 and then move the pen directly into 4, cause the residuals on the pen make it not really 4 anymore, make sense? The droplets on the pen would slightly raise the pH of the 4 solution if you did that. So before you put in the 4 solution you use a separate rinse bottle full of pH 4 over an extra jar or trash can and rinse it so it only has pH 4 solution on it.
By doing this every time you can turn on your pH pen in the 7 solution before using it and know where your calibration is at. It will be close but not quite 7 since you calibrated in pH 4 too but if it's more than 0.2 off you should recalibrate.