HM Digital COM-80 Electrical Conductivity (EC) and Total Dissolved Solids Hydro Tester, 0-5000 ppm TDS Range, 1 ppm Resolution, 2% Readout Accuracy

Great tool

Works good for me. It has the 500 and the 700 scale reading but using it in EC works for me. Plug and play easy! Feels like it was made good and the reading feel correct. Since my other reader died I'm kind blindly trusting this this is right. Good price too

High accuracy and fast reading TDS meter that supports multiple modes. I’m not an expert in water or chemistry but I purchased this at the suggestion of an online educator who does coffee and water chemistry videos. They suggested that this one was the one to get given that it has different modes that allow you to get more accurate readings than a lot of the single mode TDS meters on the market. I see it as a great value given the robust capabilities and ease of use. It has great build quality and I expect it to last a long time. My only wish is that it was easier to calibrate. It comes with calibration documentation but you need some highly specialized equipment to calibrate it. Fortunately, this isn’t necessary to do for most use cases.

Good quality never had trouble to get a reading

Works great for testing nutrient solution

Seems to work as advertised. Very fast readings, simple to use. Good purchase. The only thing I wish were different is my water. My water is further out of my target zone than I hoped! Good tool, this meter. A tool I need as I work to improve my water chemistry for coffee brewing.

Tests water for hydroponic EC measurements very well. No need to spend $100. Price point for something like this is perfect, it’s not junky but isn’t extra plastic just to charge more. Accurate and plants are thriving because of it. Thank you for no gouging.

I bought one in August 2025, and now it no longer works!

Happy , does what it says

Good EC reading

avec le recul d'utilisation, bon produit assez précis et qui fonctionne parfaitement pour ce qu'on lui demande de faire. très bien pour une utilisation non professionnelle.

Works like a charm. Fast reading (like 2 or 3 seconds) of ppm, no need to hold it for a century like a pH pen. The construction is durable, well-built. Came calibrated, which I like. Also, it has T°, which is really convenient with 3 non recirculating deep water culture buckets and a reservoir for a small flood table. Cooler res, happier plants. HM seems to be a reputable company, I would rebuy that item (well, not that I wish to do so) anytime. Buy with confidence. Excellent produit, j'ai été surpris de la qualité. Ne connaissant pas HM (et plutôt Truncheon-a-million) je m'attendais à un produit cheap en plastique qui craque quand on le prends dans nos mains. Rassurez vous, le crayon est petit, bien fait, résistant, rapide à la lecture (pas comme un crayon pH que t'essaie de tenir à quatres pattes dans une tente pendant que le PLQ est revenu 4 fois sur une décision tellement c'était long (comme cet exemple douteux)). Il est déjà calibré alors pas besoin de bouteilles de calibration, HM mentionne que ce n'est pas super nécéssaire de le calibrer souvent. Par ailleurs, il affiche la température ce qui est TELLEMENT PRATIQUE avec un système de 3 chaudières indépendantes en eau profonde. Eau froide, plantes heureuses. Quoique je ne le souhaite pas, je réachèterais (?) un crayon HM. Achetez le avec bonne conscience.

Funciona excelente, muy buenas y exactas lecturas