Comparison of 2 Basic pH Meters: Milwaukee and BlueLab


Well-Known Member
I've used the Milwaukee MW101 for over a year and a half now, but find it a little frustrating. I recently obtained a BlueLab METPH and will present a comparison of the two.

Milwaukee MW101 (MW)

BlueLab METPH (BL)

Both are basic pH meters and their sole function is to measure pH (no EC or automatic temperature compensation found in some combo meters). Both appear to function well in regards to their measuring pH.

Cost: The BL will cost a little over $150 if you shop around. The MW can be found for less than half that price. They both came with a probe and battery.

Additional Supplies: They each came with some calibration solution, but you're going to need to purchase additional 4.0 and 7.0 buffers. You will also need some storage solution for the probe. I purchased these 3 items from the respective manufacturer when I bought each meter. The Milwaukee solutions were cheaper but the volume of the buffer solutions for the BlueLab was greater, so I'll say they that the costs just about even out. I did not purchase cleaning solution for either meter.

Batteries: Batteries were supplied with each unit. The Milwaukee uses a 9V battery and the BlueLab uses 2 x AA batteries.

Probes: Probes are consumable items and will need to be replaced. I believe that they are generally warranted for six months while the meters themselves have a longer warranty. I take care of my equipment and have used the MW probe for three grows now, but I think that the response time is increasing. The MW is stated to use a gel filled probe while the BL probe seems to be filled with a fluid. The probe cord length is longer on the BL vs the MW (maybe 2 meters to 1). Both probes detach from the meters and use BNC connectors. Edit: forgot to mention that replacement probe costs for the BL and MW are around $55 and $35 respectively.

Resolution: The MW reads pH to 2 decimal points while the BL reads to 1. No big deal.

Temperature Compensation: pH measurement will vary a little with the temperature of the fluid, but it is very minor...maybe 0.02 units in the room temperature range. The MW has a manual temperature adjustment feature while the BL has no provision for temperature adjustment. Again, no big deal for my/our use.

Calibration: Both meters rely on a two point calibration at pH values of 4.0 and 7.0. The Milwaukee uses trimmer pots (screwdriver supplied) while the BlueLab uses a button. I believe that it is suggested to calibrate each meter every 30-60 days and found that the MW held up pretty well over the full grow cycle. I can't address the BL yet but I don't expect it to be an issue.

Auto ShutOff: The MW does not have one (or at least I've never reached that point) and I think that the BL turns off after 4 minutes. I'd prefer no auto shutoff and I don't like it on my vaporizer either, but I can see why it's incorporated.

Response Time: There is a big difference here and this was my reason for getting another meter instead of just replacing the probe. I was aware of this before the purchase of the MW but went with it for the price. It has a very slow response time (coming to a final, steady reading) and that may be partly due to the gel filled probe. It would usually take a couple of minutes until I was comfortable with the reading. I've only used the BL a few times so far, but the response time is far, far quicker...well under 30 seconds.

So there you have it; two pH meters that do their job well with the only real differences to me being the cost and response time. If you are on a really tight budget and don't want a pH pen, consider the Milwaukee...if you have the patience. Otherwise, just spring the extra money for the BlueLab.

If you've got another opinion on either of these meters, or have another meter in mind, please post your thoughts.
Top Bottom