Review on 🐠 Dumsamker Professional Aquariums with Temperature Range of 0 to 9999ppm by Dave Rasic

I bought three of these to lend to students for use at home and on the go. We measure water samples from the area, sometimes on site, and sometimes we bring them home (this year students are not allowed to enter the lab). These meters are correct within +/- 10% when testing commercial standards of known conductivity. Two of the three meters were within 5% and my last one shows 10% under. As long as we know the margin of error, we're fine for our teaching and research application. My students have never used conductivity meters. I used to use a Hanna meter which costs 15 times as much and whose only benefit is the ability to calibrate. It's harder to understand and beginners may not be able to handle the calibration. A Hanna-compatible calibration solution costs over $22, and this DUMSAMKER gauge costs 40% less than it would take to correct a 10-15% error in Hanna. I was also trying to get a professional measuring device working that hadn't been used in maybe 20 years. Three disappointing hours later I gave up and bought a third. Five stars for economy. Please refer to the commercial TDS/EC standard if you need high accuracy. BlueLab EC 2.77 is an example available locally for $8 to test these gauges.