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bluelab pH Pen-Digital pH Tester - Reliable & Accurate for High Yield Crops - Hand-Held Meter - Measures pH & Temperature in Solutions and Soil Solutions - Optimize Plant Health & Performance,White

  • Based on 4,657 reviews
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Availability: In Stock.
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Arrives Tuesday, Nov 19
Order within 3 hours and 17 minutes
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Style: PH Pen


Features

  • Measures pH in nutrient solution (acid or alkaline) for precise up and down adjustment with lab quality glass probe; General uses include growing tent, swimming pool, drinking water, aquarium, fish tank, and brewing.Operating temperature : 0 - 50 C, 32 - 122 F.
  • This hydroponics tester has ATC that provides consistent reading regardless of any fluctuations in temperature; Calibration reminder; Durable design for repeated uses; Fully waterproof and floats in solutions
  • Double junction electrode has a longer lifespan compared to standard probes due to less contamination and is more accurate and reliable than comparable pens, test strips, drops, and more
  • Combine with ppm meters for full indoor garden nutrients monitoring in water and soil;
  • Fully waterproof - not just water resistant; Automatic temperature compensation for accurate readings everywhere
  • Other features: Auto off function, low battery indicator, units for temperature; KIT INCLUDES: AAA battery, lanyard, and calibration solution
  • IF PROBE IS DRY, SOAK IN KCL SOLUTION FOR 24 HOURS, KCL SOLUTION IS SOLD SEPARATELY; Made in New Zealand, and manufactured by Bluelab, the industry leader in hydroponic testing equipment; 1-Year Limited Warranty with proof of purchase

Product Dimensions: 8 x 2.16 x 0.98 inches


Item Weight: 4.3 ounces


Manufacturer: Bluelab Corporation Limited - Import (NZ)


Item model number: PENPH


Batteries: 1 AAA batteries required. (included)


Is Discontinued By Manufacturer: No


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Tuesday, Nov 19

Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.

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View our full returns policy here.

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Top Amazon Reviews


  • I love it!
Style: PH Pen
First let me say DO NOT be discouraged from the one star reviews. I can understand someone being upset if they buy a new pen and get one that’s broken but if that’s the case none of us would ever own anything. It is absolutely impossible to buy anything that doesn’t have a bad review because of something that in many cases that has absolutely nothing to do with how the product works, go look up anything you own and love and someone had an issue, seriously go look and see, I’ve tried it there is nothing I’ve found that everyone loves. This pen is awesome if you are a grower and ph is vital and you want to be a next level grower. I’ve had mine 2 years and when it stops working I will immediately get another one. It does take a small bit of little effort to add a few drops of storage solution that you have to buy extra but that last a long time and it’s worth it to me. You add it after each use to keep it hydrated. If it dries out the pen is not ruined like some say but you might have to recalibrate which is easy after your first few times, especially with the step by step YouTube videos available to watch while you’re doing it. Just remember there are a lot of lazy incompetent people out there that all they want to do is push a button and be done with it and expect everything to be instant and do nothing else. It all comes down to how important ph means to you and it is very important to me. This pen is accurate and it’s awesome and requires very little effort to maintain and it has helped me take my growing to the next level. It also works great with my pool to, way better than those test strips they have that do work but not quite as accurate as this ph pen. Thousands of top growers use this pen and depend on it, you see them on YouTube all the time using it. I happened to run across the reviews looking for something else and wanted to see what the hater’s were saying and now that I’ve used the Bluelab pen a couple of years I felt I could give a genuine review based on my experience with it. So, now it’s up to you to decide. Good luck! ... show more
Reviewed in the United States on April 30, 2023 by Tony

  • Quality on the decline?
Style: PH Pen
I bought my first one almost three years ago and it was a top quality PH pen. I easily considered it the ‘gold standard’…after approximately 18 months it started acting weird…bad readings. So I looked up some reviews and saw that a years use is average…OK, I use it quite abit. So I bought another in March of 24. It just felt ‘cheaper’…but my wallet didn’t think so…. It had a short in the on/off button and would refuse to come on sometimes and at other times it would randomly come on by its self. I needed it though, so I’ve been using it. I noticed a bunch of data would show on the screen when I turned it on, like a reset, that I never saw on the previous one. Well, time went by and it never asked to be calibrated…my first one would remind me about every 30 days. This seems to have something to do with that ‘reset’ data I see everytime in get it to come on. So the other day I tried to calibrate it and it wouldn’t do it…just kept displaying the odd data on the screen. Did I get a Friday model? Is there anything that can be done? Warranty wise? $100 is a lot of money to me, especially for something that now feels like a toy version of its former model… ... show more
Reviewed in the United States on July 16, 2024 by Fishnjnz

  • PH pen
Style: PH PEN + CARE KIT PH
Blue lab is the only brand of meters I will use from now on. I have used 4 other ph pens and I wish went with blue lab first, I would have saved time and money. 30 day calibration reminder is a life saver also. ✌️
Reviewed in the United States on September 26, 2024 by Alan Meade Alan Meade

  • Read the Instructions
Style: PH PEN + CARE KIT PH
I was a little hesitant to purchase even though I've had really good luck with this company based on the reviews. Like I've heard so many times in life, common is not so common. If you purchase this item, please read the instructions. You cannot simply pull it out and calibrate. You must soak it in the solution for 24 hours and then calibrate. Do not go cheap unless you are okay with mediocracy. ... show more
Reviewed in the United States on March 13, 2024 by Deric Frisbie Deric Frisbie

  • Worked Great For a Year - Now Won't Calibrate
Style: PH Pen
This PH pen worked perfectly for about a year. Then, I started getting readings from the meter from our tap water, which is about 9.2. Meter shows 3.7 with out tap water. Watched the Blue Lab calibration video, followed it to a T, but no luck. I bought the pen, bought the calibration pen, and the first time I tried to calibrate this guy, she's stuck on 3.3 or sometimes 8.7. We do not appreciate spending big money on a "lab" PH device, only to find out it won't calibrate. Like the other One and Two star customers who have had the same experience, this thing is not worth the high price they ask for it. Soaked in KCL solution, and we've kept the tip clean and soaking in KCL since we bought it. One Star for the Blue "Lab" Pen that is not a laboratory-quality device. #LessonLearned ... show more
Reviewed in the United States on February 15, 2024 by Catch22STL

  • Blue lab ph meter
Style: PH Pen
I purchased this blue lab pH meter over a year and a half ago it's worked amazing I've had no issues whatsoever easy calibration great value on Amazon shift with no issues whatsoever I highly recommend
Reviewed in the United States on August 14, 2024 by Thomas Popke

  • Hard water
Style: PH PEN + CARE KIT PH
This is great when you know you’ve got hard water and you want your garden to have more of a balanced ph watering. Works within seconds of adding any upper or down. Design is simple and easy to manipulate when creating solutions.
Reviewed in the United States on September 13, 2024 by Allyssa

  • quality
Style: PH Pen
This is a very nice product. Extremely accurate and easy to use right out of the box. It has a bright led backlit display and comes with a removable cap to keep the sensor dust-free and safe while not in use as well as a small lanyard to hang the tool from for easy accessibility. If you can afford it. I highly recommend getting this over a cheaper version. When your dealing with Ph accuracy and dependability trump cost. ... show more
Reviewed in the United States on December 20, 2023 by John

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