bluelab pH Pen - ± 0.1 pH Accurate, Durable Double Junction Probe, Waterproof & Floats, Auto Temperature Compensation, Easy Calibration - Made in NZ
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Availability:
In Stock.
Arrives
Tuesday, May 12
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Style: PH Pen
Features
- Perfect pH control for various media - ph meter for water hydroponics can be used for growing tents, swimming pools, drinking water, aquariums, fish tanks, and brewing. Our pH meter provides a quick and handy way to manage the success of your crops. Helps you ensure that pH and temperature are always in the optimal range for maximum uptake of nutrients. *Note: readings in tap, reverse osmosis (RO) or distilled water may be slow and/or unstable due to insufficient dissolved Ions (salts).
- Easy calibration - Set up our digital pH meter with a two-point calibration process. Calibrate the handheld meter before first use. Each digital pH meter for soil and water comes with a 30-day calibration indicator that can be viewed on a backlit LCD display. The kit includes one 20-ml sachet of each pH7, pH4, and KCl for initial hydration and calibration.
- Get accurate readings with a double-junction probe. Unlike glass bulbs, the double-junction probe minimizes contamination. Hence, it helps in improving precise readings and has a longer lifespan. This pH pen has automatic temperature compensation for an accurate temperature. Our pH meter for water hydroponics will take measurements in increments of 0.1 pH.
- Top-notch design and manufacturing - This digital pH meter for water and soil is available with an auto-off function. It has a low battery indicator and "C" and "F" units for temperature. Instructions are on the backside of the pH pen. The kit includes an AAA battery and a lanyard for a hands-free option. The pH tester is easily accessible and won't get lost during use or movement.
Product Dimensions: 8 x 2.16 x 0.98 inches
Item Weight: 4.3 ounces
Manufacturer: Bluelab Corporation Limited - Import (NZ)
Item model number: pH Pen
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, May 12
Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.
To initiate a return, please visit our Returns Center.
View our full returns policy here.
To initiate a return, please visit our Returns Center.
View our full returns policy here.
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Similar Products
Top Amazon Reviews
Style: PH Pen
This pen is a little pricey but remember you get what you pay for. It works great and it’s easy to calibrate, If you need a quality ph meter this is the one,
Reviewed in the United States on February 1, 2026 by Walter W. Baldree
Style: PH Pen
This meter was a game changer for me, took a lot of stresses away since I live and die by accurate ph readings for growing them trees! High quality piece here that I (beyond) highly recommend this product! Easy to use on every level.. easy calibration with great directions to get you going. Speed and accuracy…love the fact it tells you when you got it calibrated correctly and also when it needs it again! 10 stars ⭐️⭐️⭐️⭐️⭐️⭐️⭐️⭐️⭐️⭐️
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Reviewed in the United States on January 7, 2026 by Bigfysh93
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!
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Reviewed in the United States on April 30, 2023 by Tony
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…
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Reviewed in the United States on July 16, 2024 by Fishnjnz
Style: PH Pen
Seriously save your money. I keep seeing this pen routinely recommended for some reason as it was to me and decided to write a review to at least save some people some money. Stop buying this overpriced pen!! Its insane what this costs now. I admit I am bitter about it as I truly feel I got ripped off. I run two hydroponics gardens and two aquascaping fish tanks, both with pH sensitive shrimp species. I also run C02 to the fish tanks to help grow the plants, which lowers pH throughout the day. In fact, one of the ways to tell what your C02 concentration is by the relationship between pH of the water and KH (another test), but my point is simply that pH is important to me, and I am just mentioning it to prove I know a thing about water chemistry to say the least. This Bluelab pen is slow to respond at best, but totally way off at worse. Even after calibration it just can't be relied upon to give me accurate numbers. I use a cheapo pH meters and those give me consistent and accurate results. You can buy 5 of those and get better results than this pen gives! Better yet, at least on the aquariums I also use a basic API pH test kit, (where the water color changes based on PH) and again side by side the accuracy of that is hands down better than this pen. Is it possible I just got a bad pen? Maybe. I am aware of the "rules" on the pen - do not let it dry out, store the bulb in the proper solution, rinse it well before using, and pro tip - make sure to tap it so any air bubbles in the bulb float up and do not impact results. But even through all that, it calibrates fine, leads me to believe it will work and then goes wildly off. It cant be trusted. I do not like to write bad reviews but between the cost and my experience I am just hoping to help others. Go buy the $15 ones.
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Reviewed in the United States on December 11, 2024 by Matt W.
Style: PH Pen
I have been using these for over 10 years so I know how to use it. It’s just stuck at 7.0 no matter what. Calibrated 2 times. Nothing. The one I bought over an year ago also stopped working so now I have just purchased a third one so I can return it and if this one doesn’t work, I’ll never use blue lab again unfortunately! Update. Blu lab returned my money. They still have me as a customer.
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Reviewed in the United States on January 8, 2025 by Josh
Style: PH Pen
Love my blue lab have used for years easy calibration and accurate. Buy the calibration and storage solution to maintain this product and have great long term use. The led screen is easy to read and displays water temperature. Functions fantastic
Reviewed in the United States on August 3, 2025 by Raymond