do the digital ph pens need to be stored with water in the cap

[Danks2005]

I store my Milwaukee in 7.0 calibration solution. They are stored dry on the shelf, then you condition the elecrode when you take it out of the box. Once conditioned, letting the electrode dry out will damage the meter. This is how I understand it anyway. The instructions for my meter said to store it in either storage solution or 7.0 calibration solution. So, since I always have calibration solution I don't see the point in buying storage solution.

 

[qupee]

Actually Qupee, the instructions I have for the Oakton pH2 say..

"For long-term storage, fill the cap with 20 mm of storage solution (NOT de-ionized water), and replace cap*. This will keep the sensor conditioned and ready for next use."

Huh, you're right. Can't believe I missed that, pulled up the manual pdf and re-read it before posting that even just to make sure I wasn't posting bad info, lol.

It does also say, though:

To maintain tester accuracy, use tester regularly or
calibrate at regular intervals as required • For long-term storage, fill ...

And I use mine pretty much every day.

I have been thinking of getting a new one just because I've had it so long now (but it checks fine with calibration solution every time). When I get a new one I'll probably store it in solution and see if I notice any difference.

Does anyone know, if your meter reads 7.0 & 4.0 calibration solution accurately, can you assume you are measuring 5-7 range for nutrient solution accurately? I would think so, but not totally sure. Do all meter probes work in the same way, made the same?

Good info in that link, too, Hammerhead.

 

[NiteTiger]

I never kept mine in any kind of solution or water, I just used it everyday

Long term storage? Pffffft!

 

[Hammerhead]

If you get a cheap pen then its up to you. I spent some $$$ on that Blue lab so i'm going to take very good care of it... A replacment probe for it is 50$

 

[FreezerBoy]

??? I think you have it backwards

avoid storing in distilled water because it will deplete the hydration layer of refillable electrodes, and decrease the life of nonrefillable electrodes.

Whoa, did I drop the baby. I have NO idea of proper pH pen care! Do NOT listen to me in this matter. My comment was just on mineral buildup in general. I have NO idea of proper pH pen care!

I need to learn though. I actually got one today. An ecoTester pH1. Because of recent move, I've gone from reading one tub twice a month to five tubs twice a day. Suddenly the concept of a pen is more appealing to me.

 

[Hammerhead]

I use my Blue lab when I mix up new batches(1-2 weeks between uses).. Im not storing long term but after I use the probe it does get put back into its holder with Storage solution until I need it again.. Long term storage to me is more then a week..Might be different for others..Weather your using it or not you should keep the probe tip wet at all times..

 

[marrdogg]

My Oakton EcoTestr pH2 does not state that it should be stored in solution.

I have been using mine for nearing 18 months now, never stored in solution. It needed recalibration once after replacing the batteries (also needed only once so far, after close to a year).

I also have a Oakton EcoTesterph2, I never store in solution just rinse in tap water after use and stand up to dry. Hell I never even put the cap back on it, been using it this way for over a year. Calibrate it ever so often with 7.0 and 4.0 calibrates like a champ every time. Peace!

 

[qupee]

I also have a Oakton EcoTesterph2, I never store in solution just rinse in tap water after use and stand up to dry. Hell I never even put the cap back on it, been using it this way for over a year. Calibrate it ever so often with 7.0 and 4.0 calibrates like a champ every time. Peace!

Yep, my experience exactly.. I figured the Ecotestr is barely more than a new probe for an expensive meter. If I do ever have problems it's cheap enough just to order a new one.

Last night I rinsed mine in hot water for a few minutes and then let it soak in 4.0 cal. solution for a couple hours. It seems to settle on a reading faster now. Could be my imagination, or the brownies.

 

[marrdogg]

Yep, my experience exactly.. I figured the Ecotestr is barely more than a new probe for an expensive meter. If I do ever have problems it's cheap enough just to order a new one.

Last night I rinsed mine in hot water for a few minutes and then let it soak in 4.0 cal. solution for a couple hours. It seems to settle on a reading faster now. Could be my imagination, or the brownies.

I'm gonna tell you something though,I had the ph1 before this one and couldn't do the same things as I can with this one. When the ph1 would dry out it would mess the calibration all around. It would not calibrate it just tell me or(outta range). I did however find something to remedy this don't know how long it could have been done before the electrode just went. I would take the meter and soak it in lemishine which is for hard water in your dishwasher, I know harsh but it would work,after soaking and a mild clean it would calibrate every time.

 

[Herbophile]

What is the difference, if any, between calibration fluid and storage solution?

 

[petemoss]

What is the difference, if any, between calibration fluid and storage solution?

I think there is a difference. My Oakton PH2 used to get a gel-like mold in the cap when stored in calibration solution. With storage solution, there is no mold, so I think there are some added ingredients in the storage solution.