Bluelab pH PenPlus

Finally, the people have spoken and Bluelab listened! We all grew tired of the throw away pens they made in the past, now you can replace the probe which helps extend the life of this tool and justify its cost.

The only caveat is that you have to soak the probe in the KCI solution for 24 hours before using it, so just do that right away when you get it and keep some KCI solution in the cap to keep the probe in good shape.

The battery life is amazing, so far I have used it on a daily basis and not had to change out the batteries. It is super easy to use, accurate (once calibrated) and it can be used for everything like tap water quality checks to hydroponics to aquariums etc. It is a very versatile tool. I have decades of hydroponics experience using tools just like this so I know a quality tool when I see it. Considering how well built and durable it is, and how affordable it is, I can recommend this item with confidence.

A month ago I ordered this Bluelab pH PenPlus to review just after ordering a cheaper $27 red pH meter. Imagine my luck. I decided to run both of them side by side while setting up new fish tanks, where I needed accurate pH to keep my fish and shrimp alive. I also threw an API test kit and pH test strips into the mix. That gave me a lot of side by side data and a pretty honest answer to the question of what you actually get for the extra money.

Out of the box you calibrate the Bluelab using the included 7.0 and 4.0 sachets. The process is simple and printed right on the back of the meter if you forget. Once calibrated, you turn it on, dip it, swirl it around a little, and wait for the numbers to stabilize. You get pH and temperature in under 30 seconds. It is so easy that I found myself checking the pH on all my tanks more frequently than I normally would because I did not have to fill a plastic vial or read a color chart. I am sure my shrimp appreciate that. The backlit display is easy to read and the build quality feels premium throughout. There is a rubber boot to protect the probe and a lanyard included to keep you from dropping it in the tank.

On build quality alone the Bluelab has the red meter beaten, side by side the devices look like a VHS next to a DVD, but that is where the arguments for the BlueLab meter end.

The cheaper meter delivers pH and temperature just as fast. It also includes TDS and EC measurements, which the Bluelab does not offer on this unit. For aquarium keeping TDS is genuinely useful — I used it to measure water quality before and after installing a reverse osmosis filter and could actually quantify the improvement. Both meters have replaceable probes, so that feature the Bluelab promotes heavily in their literature is not the differentiator they seem to think it is.

The calibration solution situation is worth calling out too. The cheaper meter required three point calibration using 10, 7 and 4 solutions, which is more involved than the Bluelab's two point process. But the cheaper meter came with its calibration solution in resealable containers you can put back on a shelf and use again (and there's a lot of it). The Bluelab ships with satchets that you tear open. Whatever you do not use you could store for recalibration but there isn't enough of it to make that worthwhile. Maybe the solution goes bad when exposed to air? I don't know, but I like having extra calibration solution on hand as these meters do need to be recalibrated periodically.

With less functionality and no real name recognition (that I'm aware of) to justify the gap, a $90 premium over the cheaper red meter is a hard sell.

I got this pH tester to use for gardening/soil tests. Honestly it's probably overkill for what I'm using it for, but it is really nice and I believe it to be accurate.

When you first get it, you have to hydrate the tip by soaking it in the provided liquid. Then you calibrate it using the calibration solutions. Then it's ready to go!

The probe on this meter is replaceable which is really nice. It means I'll be able to use this meter for a long time to come. It's easy to use and read, and has a professional, quality feel to it.

Right away, this pH meter feels like a tool made for actual use. The display is easy to read, and having calibration and storage solution included makes it easier to use correctly.

I appreciate tools that do not make setup feel like a project. This one feels practical, sturdy, and clear enough to use without second-guessing everything. The replaceable probe is a nice feature because it makes the tool feel more useful long term.

The included solutions make proper care and calibration easier from the start. The backlit display is readable even when the lighting is not perfect.

It feels like a serious tool without being intimidating.

This is best for someone who needs to check pH regularly and wants the calibration pieces right there from the start. The readable display, included solutions, and replaceable probe make the 5-star rating feel supported.

The Bluelab pH PenPlus is a serious upgrade from standard testers, especially because the probe is replaceable. Most meters become useless once the sensor fails, but being able to swap out just the probe extends the life of the tool significantly.
​Out of the box, calibration is simple and straightforward. The kit includes the necessary calibration solutions and KCl storage solution, which is essential for keeping the glass probe healthy and accurate. The backlit display makes reading measurements effortless, even in lower light conditions around reservoirs.
​The IP68 waterproof rating provides peace of mind against accidental drops into tanks. Readings lock in quickly for both pH and temperature, making regular nutrient monitoring fast and reliable. It feels solid, performs consistently, and the build quality matches expectations for a premium tool made in New Zealand.

I needed a new PH pen as my last one finally bit the dust.

I use a PH pen for a few things around the house.
First is my hydroponics and plants, and second, when I'm mixing new saltwater for my reef aquariums.

I needed a pen that was fairly accurate
One that's easy to read and has a hold function.
Has a temperature function on it
Of course, waterproof

This pen checked all of my boxes and a few extras.
One key selling point is the replaceable probe. Rather than having to buy a new pen in the future, I can just replace the probe at a much cheaper price.
It's easy to use, easy to calibrate and very easy to read the display.
It has a 30 day calibration reminder so you don't forget to calibrate it and keep up the accuracy.
It comes with everything you need, including batteries, high/low calibration fluid and storage solution.
It may be priced slightly higher than similar pens but with the replaceable probe, build quality and ease of use, it's money well spent.

The pH probe is a practical and dependable tool for anyone who needs accurate pH and temperature readings in water-based environments. Its ability to measure both pH and temperature at the same time makes it especially useful for hydroponics, soil growing, aquariums, brewing, and other nutrient or water management tasks where precision matters.

One of the most convenient features is the replaceable probe design. Instead of replacing the entire device when the probe naturally wears out, you can simply swap it out. This helps extend the life of the meter, reduce downtime, and keep it performing consistently over time.

It’s also built for tough environments. The device is both dustproof and waterproof, making it well-suited for wet grow rooms, mixing tanks, and frequent hands-on use around nutrient solutions. This durability adds confidence when working in demanding conditions.

The bright backlit display makes readings easy to see, even in low-light environments, and the simple two-point calibration process helps maintain accuracy without unnecessary complexity. The 30-day calibration reminder is a helpful touch that ensures consistent performance.

Overall, the Bluelab pH PenPlus is a durable, accurate, and user-friendly tool that takes the guesswork out of pH monitoring and is well-suited for both hobbyists and more serious growers.

The Bluelab pH PenPlus is an excellent tool for anyone who needs accurate and reliable pH readings, especially for my Koi pond. It’s very fast and easy to use right out of the box, and the quick two point calibration process is straightforward, making it simple to maintain precision over time.

The build quality stands out immediately and it feels durable and well-designed, and the IP68 waterproof rating adds peace of mind when working around liquids. The backlit display is clear and easy to read, even in low-light conditions, which is a nice touch and totally worth the money.

This Replaceable Probe pH and Temperature Meter is like a friend who's always there for you when you need to test water. It is waterproof so you can drop it in water. Splash it and it will still work.

The display on this meter is very bright, so you do not have to strain your eyes to see what it says. The Meter is also very easy to use you just need to do a 2-point calibration, and you are good to go. It is so easy that it feels like it should have a warning that says you are doing everything right.

This Meter comes with its special solution to help it work properly so you do not have to go out and buy anything else. This means you can just relax and use the Meter without any problems.

The best thing about the Meter is that you can replace the probe when it gets old. This means you do not have to throw the whole meter, you can just get a new probe and it will be like new again.

This Meter are made in New Zealand you know it is very strong and well made. The people who make the Meter are very good, and at what they do they make sure it is perfect before they send it out.

This pen is pretty high tech and awesome. I don't do hydro, but I'm into soil grows. (nothing can replicate the deep flavor notes and even some neat colors you get from soil, IMO.)

The probe is thin but sturdy, easy to insert into soil without leaving a big crater.
Fast and easy results, easy to calibrate too.
The garden supply stores near me have pens that aren't this nice and they sell for more! (smh)

I've been using this to help gauge my soil quality and getting it back to normal after I had to use a neem drench and biologics to get rid of a pest apocalypse. (gnats, mealybugs, then mites.)
This can help you gauge whether or not you need to replace your soil completely, or just keep augmenting and trying for a re-balance.

I do wish it came with a carrying case, but I'm currently searching for a good one. I'll come back and post it here if I get it.

PS: Don't ever do neem soil drenches. It didn't help me with fungus gnats; it just turned the soil into a rock-hard mess that I'm going to have to replace. Neem foliage sprays during dark cycles are still good!

The Bluelab pH PenPlus turned out to be much easier to use than I expected. I’m not highly experienced with pH testing equipment, so I appreciated how straightforward the setup and operation were right from the beginning. The instructions were simple to follow, and the readings appeared quickly and clearly on the display.

The compact size is another major advantage because it stores away easily without taking up much space. The lightweight design also makes it comfortable to hold while testing. I especially liked the backlit screen since it makes the numbers easy to read even in lower lighting.

This meter feels well made and dependable. The waterproof construction adds an extra layer of reassurance when using it around liquids. The included calibration and storage solutions are a thoughtful addition and help make the entire kit feel complete right out of the box.

For anyone looking for an effective pH meter that isn’t overly complicated, this is a solid option. It performs accurately, responds quickly, and feels designed with convenience in mind. The pricing feels fair considering the quality and included accessories. Plus, the delivery was fast as well since it arrived within two days.

This pH and temperature gauge is a really nice little tool. It’s a great portable size, easy to handle, and the display is clear enough to read. Setup and use are straightforward, and it seems very accurate so far.

I like that it measures both pH and temperature, which makes it practical for hydroponics, aquariums, brewing, or general water testing. The replaceable probe is also a big plus because you don’t have to replace the whole pen when the probe eventually wears out.

Overall, this feels well made, simple to use, and reliable. Definitely a handy gauge to have around if you need quick, accurate readings. Recommend!

This Bluelab pH PenPlus is a more serious pH meter than the cheap little testers that are all over the place. It measures pH and temperature, has a backlit display, and includes calibration and storage solution, which is important if you actually want reliable readings over time.

The replaceable probe is one of the better features because pH probes do not last forever. Being able to replace the probe instead of throwing out the whole meter makes this feel like a better long-term tool. The waterproof rating is also reassuring since this is obviously going to be used around liquids.

This is a good choice for hydroponics, plant care, aquariums, brewing, pools, or any situation where pH accuracy matters. It is more expensive than a basic tester, but it also feels more like a real instrument than a disposable gadget.

Grabbed this pH pen for monitoring nutrient solutions and water in the garden, and it’s been a fairly reliable and accurate tool. The replaceable probe is a big plus, the display is easy to read in any lighting, and calibration with included solutions makes it straightforward to keep accurate. Only small gripe is the probe cap and storage solution add a bit of extra maintenance to keep it in top shape, but that’s standard for quality pH meters. Been using it a couple weeks with solid results.

I’m using this for my pool rather than plants, and it has worked great. The readings are quick, easy to read, and consistent, which makes checking and managing pool pH much easier than relying only on test strips.

The build quality feels great, and it is obviously waterproof. The display is bright and clear, calibration is straightforward, and the included calibration and storage solutions are great. The instructions to calibrate and use are straight forward.

The replaceable probe is also a big plus because it makes this feel like a longer-term tool instead of something disposable. It may cost a bit more than cheaper pH pens, but the accuracy, durability, and ease of use make it worth it - overall it seems like a great value for the money if you are looking for instant accurate PH readings.

The replaceable probe design on this pH pen is a major plus, as it prevents having to discard the entire unit when the sensor eventually wears out. The meter is built well, completely waterproof, and floats if dropped. The backlit display is easy to read, and the dual pH and temperature measurements are fast and stable. Calibration is straightforward with the included solutions, and the 30-day reminder is a helpful touch for maintaining accuracy. It is priced higher than entry-level options, but the build quality and logic of a replaceable probe make it worth the expense.

Very easy to use, gives fast and accurate readings, and the replaceable probe makes it feel like a long-term investment instead of a disposable tool. I also love that it measures both pH and temperature, which saves time and keeps everything streamlined.

The display is clear and easy to read, calibration is simple, and the build quality feels solid and professional. I’ve used other pH meters before, but this one stands out for its reliability and consistency. It’s compact enough to carry around but durable enough for daily use.

If you want a dependable pH meter that takes the guesswork out of monitoring water quality, this meter is absolutely worth it.

This Bluelab pH PenPlus is a high-quality handheld meter that delivers fast, reliable pH and temperature readings with excellent consistency. The replaceable probe design adds long-term value and the waterproof rating makes it suitable for demanding environments like hydroponics or nutrient solution testing. The backlit display is clear and easy to read, and the 2-point calibration process is straightforward, especially with the included calibration and KCl storage solutions. Readings stabilize quickly, which makes routine monitoring efficient and easy. Overall, it is a dependable and well-built meter at a great value.