American Marine PINPOINT Salinity Monitor + Calibration Fluid

Need a 9 volt battery. Also need a fine precision (flat not Phillip) screw driver to calibrate. This is not provided with the purchase.These are sold in precision screwdriver sets easily available. The calibration screw is listed as screw 3 inside the battery holder on the photo in the instructions. Don't mess with screw 4 as this is factory set (glued per instructions to keep from accidentally trying to set). Screws 3,4 are right next two each other with screw 3 further from the edge of the battery box. Instructions are clear. Calibration fluid provided. Up and running in less than 2 minutes. Display stabilizes making reading easy. Conversion table to specific gravity included. Highly recommended.

I use it regularly to measure salinity in my Reef Tank and when I mix new saltwater. It's especially helpful when mixing new saltwater, since I just add salt until I reach the desired salinity, which is much easier than a refractometer. Generally it is pretty accurate if you make sure to do a few things; 1. Let the sensor be in the water a few minutes before taking a reading, 2. Swish the sensor around a bit (this make a big difference), 3. Only use a fresh battery, not the AC adapter, and make sure to turn it off after every use to save the battery. 4. Carefully calibrate it with the fluid provided.

These work well, however, be careful handling the probe as the cable entering it is rather fragile. I had to replace the last one due to internal wire breakage, they are very stiff and damage easily over time. My last one lasted about 2 years but now that I understand the failure will handle the replacement more delicately

wow, I have just bought this meter last week and today went to check the answers to my question. And there was a brand new review posted on October 6 by Bob who clams that the meter does not hold calibration. Immediately after reading it I decided to check. And what do you know, the meter was 3 points off. I calibrated it again and after using it for 10 minutes the reading was off again by 1.6 points. Thank G_d I've read Bob's review, otherwise I would be completely oblivious to the fact that the meter is giving me wrong information and would be stuck with this junk.

I love the meter, love it. It works well, holds calibration for me.My problem is how sensitive the device is to water. The probe can be fully submerged but the monitor itself can't even be in the same room as water.I sent the unit back for repair - which was reasonable - and was warned that it had gotten wet and I needed to be more careful. Aside from maybe picking it up with wet hands, I never got it wet, never spilled on it.UPDATE: I solved the problem. Put the monitor in a ziplock bag. Since then it's stayed totally dry and fully functional.Ok, for round two I have been so very very careful to keep it away from water. Not a drop has touched it. Sadly, it stopped working this morning. I opened it up and found corrosion all around the switch.If it was $10 more expensive and included a waterproof switch, and an o-ring around the housing it would be a perfect product. I know electronics and moisture don't mix, but a product designed to be using in and around water needs to have a few protections against moisture.

Titile says it all. It is a good precision instrument. I had to replace mine after 10 years...wife was playing fetch with our puppy and they knocked it into a large bucket full of sea water. It was a great death.

I can't believe I have been using hydrometers and refractometers all this time.Got the pinpoint portable salinity monitor and I will never look back.

I love that they include the calibration fluid with this unit. It gives me more confidence in my aquarium's salinity measurements. Initially, I thought i was low in Mg and Calcium but it turned out that my refractometer wasnt accurate. No longer! I can confidently measure no matter the temperature as this is adjusted accordingly. The only reason I didnt give it 5 stars was the fact that I had to calibrate more than once so far.