Old Reviews Review - HM Digital PH-200 Waterproof pH Meter

[DubV]

Great review Andy! I purchased one because of this review and received it last night. I followed Andy's recommendation and got the 4.01 calibration solution and my unit is exactly like his. If you calibrate in 7.0 and then tested it in 4.01 it comes up at 3.91 but if you do the reverse it is dead on. Great tip Andy and a very good product in my opinion!

 

[JR Vette]

Thank you for the review. That sounds like a resonable price, and the old saying " you get what you pay for " sounds true in this case also

 

[AndyBotwin]

Bumping an OLD thread with some more info about this one. After disbanding my grow space one of the few things to survive was the HM PH-200 meter. I dug it out the other day and of course the sensor was dry as the storage fluid probably dried up a year and a half ago. Expecting the worst, I scraped off the excess dried crystals and left it overnight to soak in some storage solution. Today I washed everything with distilled water and threw it in some 7.0 calibration fluid. It showed 6.75 which ain't half bad. Caibrated it once with the 7.0 and it got better, calibrated it again with some 4.01 solution and it was dead on. Put it away for 8 hours, tried it again, dead on accurate within about 5 seconds. Needless to say I'm impressed with the durability of this thing and I'm happy to not be spending $30 on a new sensor. :dance2:

 

[briman]

Just got one last week after my Hanna combo took a shyte. This will be my "goto" meter and got a replacement probe for the Hanna for my backup! Great review Andy!

 

[realtree]

i have a ph-200 meter it will not read nutrient solutions if i use RO water does not read when i use organics my town uses a RO system for tap so thats a no go does not read low ppm well water or rain water it reads milk cola baking soda orange juice calibrates perfect just don't work for growing plants i sent it back to hm digital they said it was perfect. so i have a meter i cant use a wast of money! i test the ph drops for color using a calibration solution and go with that.

 

[AndyBotwin]

i have a ph-200 meter it will not read nutrient solutions if i use RO water does not read when i use organics my town uses a RO system for tap so thats a no go does not read low ppm well water or rain water it reads milk cola baking soda orange juice calibrates perfect just don't work for growing plants i sent it back to hm digital they said it was perfect. so i have a meter i cant use a wast of money! i test the ph drops for color using a calibration solution and go with that.

Hey bud, not sure what the issue is but I've been using mine with RO water for years. What do you mean with you say it won't read?

 

[realtree]

false reading. or the reading stays the same regardless of the amount of PH up or down i use. for example nutrient solution ph of 6. milk about 7 calibration solution ph of 7. i can put the meter in calibration solution reads 7 then put in milk about 7 then nutrient solution about 7 but it is really 6. no matter how much ph up or down i use the meter still reads about 7 them back to the milk and calibration solution reads right. tried ro water tap water mineral water river water this meter does not know the difference but it reads pepsi root beer perfect. who knows

 

[briman]

false reading. or the reading stays the same regardless of the amount of PH up or down i use. for example nutrient solution ph of 6. milk about 7 calibration solution ph of 7. i can put the meter in calibration solution reads 7 then put in milk about 7 then nutrient solution about 7 but it is really 6. no matter how much ph up or down i use the meter still reads about 7 them back to the milk and calibration solution reads right. tried ro water tap water mineral water river water this meter does not know the difference but it reads pepsi root beer perfect. who knows

Buy yourself some cleaning solution, soak it in the cleaning solution for 2 minutes and no longer. Rinse with RO or tap water and recalibrate. If that doesn't work, you may need a new lower probe. I actually get a better calibration with the lower ph test with the 4.01 and it reads just fine. try that and let us know.

 

[realtree]

thanks for your advise! i tried just about everything even sent the meter to HM-digital they checked everything and said it worked perfect and was in factory new condition. i dont know what to say. do what you do for the love

 

[Duckster]

I have used many pH meters in my career and this is the best pH pen that I have ever used. I purchased this one because you can change out the sensor. I have been using mine for over 2 years and it still calibrates fine and responds quickly. I generally don't get much more than 1 year from a pH sensor. This pen is a best buy in my book.