Bluelab Combo Meter for pH, Temperature & Conductivity in Water - Easy Calibration, Digital EC/TDS/PPM Tester for Hydroponics & Indoor Plants (METCOM)

I was not having any luck finding a decent & reliable ph meter. I wanted to wait a while before writing a review to make sure. The probe arrived with a little solution but it looked like the storage cap was not tightened enough but at least it did not arrive dry. The calibration solution was included in 20ml package, enough for one calibration but if you have a an empty bottle and you use distilled water when calibrating you can use the same solution a few times. It calibrated easily, probably one of the easiest calibrations compared to others I had, all you do is put the probe in 7.0 solution and press and hold CAL, thats it & the same for the 4.0 solution. After the first week the ph started drifting a bit but I was using it several times a day due to switching to different brand of nutrients for my peppers, I was learning a new routine and this ph meter made it so easy. I calibrated it again on day 6 and I'm thinking it was due to being new; it's held the calibration for about 24 days before it started drifting ( +.1 ) that was with me using it once a day and twice a day every 7 days when I change my water. It reads the ph fast and stays stable regardless of how long it stays in the solution. It also checks the temperature but I'm consistently in the sweet spot so don't use that feature much. The attached TDS/EC nutrient meter is a bonus, it reads all of them. I prefer using the 500ppm scale, but if you prefer EC, it's there too.It's convenient in my Aerogardens, fits in the holes perfect which is why I love it even more. I got a cheap bag to carry it around, I recommended something with a lanyard or strap so that you don't drop it if you have to carry the meter with the probe in water. I wash the probes in tap water after every use and change the storage solution after every 3-5 uses. I've never used distilled water although I'm sure it's better to rinse in distilled water instructions say tap water is perfectly fine. I recommend you get KCL storage solution and calibration solution 4 and 7 while your at it. If you don't have KCL solution you can use the 4.0 solution to store the ph probe while you get the KCL storing solution. If you have access to a hydroponic or grow store buy the calibration solution there it may be cheaper by a lot.This is overkill for what I have growing, definitely commercial quality but I love that it works, and it does what it does perfectly. I no longer double check the ph with other meters I trust these readings. I highly recommend this meter & Bluelab.

The BlueLab METCOM is a nearly perfect instrument (at least in the short term). It does what it's expected to, within it's limitations. BlueLab doesn't claim it to be any more or less than it delivers. PH seems very accurate. I calibrate often and it never seems to need it, despite the fact the probes are in a nutrient tank 24/7 (I do give the probe a day a week or so in Kcl solution to hopefully keep it healthy). The TDS meter is fine for it's intended use - nutrient solution maintenance, but isn't precise enough to gauge the quality of raw/RO/DI water, you'll want a cheap pen for that, I use a Membrane Solutions TDS pen and it seems quite accurate down in the sub teen TDS levels (less than 20 bucks and comes with a nice magnetic case). The Thermometer is slow to respond (built into the TDS probe and has high mass) and ok as a very rough idea, but mine is about 3 degrees F high and it only reads full degrees (no tenths). Here my goto is the VEE GEE Scientific 83110 which is a great thermometer (see my review on that). The BlueLab thermometer is plenty accurate and repeatable to tell if you have a chiller problem or such. I don't like not having a comparison/backup for everything, so I just ordered a "2 in 1 Temperature pH Monitor" (Amazon of course) for about forty bucks (20 less than a probe from BlueLab), review in a month or so. (it's 7/21)This unit lets you check in on your Hydro system anytime you wish with the press of a button per reading, 3 hits and I've got PH, TDS and Temp, and I know it's all OK or if I need to look into a problem. No rinsing, opening tanks, checking calibration or any of that pen stuff, and zero risk you'll drop the pen in. The whole PH pen thing is just a PIA and discourages frequent checks. The pens are less precise in general unless you spend almost as much as you will for this handy device, and the probes are often not replaceable. Ph probes by design have a limited life. Always keep litmus paper or a dropper kit on hand, JIC.BlueLab products are moderately priced, very reliable and fairly accurate (but highly repeatable). That fits the needs of a lot of users. If you are a fit, this is a great solution, I am, and I will be using BlueLab instruments in the future.

Works well very happy with it.

This is my second Bluelab combo meter. The first one functioned great for almost 2 years, then stopped registering voltage changes on the pH sensor. Purchased multiple replacement pH sensors and still refused to change readings despite going into both calibration solutions. Purchased a new combo meter in October 2024 and it worked fine until today where the same exact issue happened again. Tried using 2 other brand new sensors and no change in readings. Ofcourse it happened right after return window. This is far too expensive of a sensor to be failing this early. I have 10 year old Hanna stick pens that still work and cost a fraction of the price. Will not be buying again. Do better.

Fast delivery, quality products