Vee Gee Scientific STX-3 Handheld Salinity Refractometer with ATC, Industrial-Grade, 0-100% Salinity Range, 1.000-1.070 Specific Gravity Range, 5-Year Warranty

Great refractometer. I compared it to a couple of cheaper ones I have and an electronic. The scale on this one is easy to see, stays in calibration and has some weight to it. Only thing I wish is the case was a hard case but it is a nice soft case. For those that say they did not get a screwdriver, did you look in the velcro pocket inside the bag? That is where I found mine.Thanks for a great product.

I have a Neptune Systems APEX Controller for my reef aquarium that measures and reports salinity (conductivity) in real-time, but I still rely on the VEE Gee STX-3 Refractometer as the final word on what the salinity actually is. I check the refractometer's calibration before each and every use with Refractometer Calibration Solution made by Aqua Craft Products and the refractometer reads exactly to the standard and I haven't had to adjust the calibration yet. This gives me confidence that the STX-3 is consistently accurate and holds calibration. I just threw-away a Red Sea refractometer (sorry to have to use names) that I purchased about a year ago ($50 - $60) that wouldn't hold calibration for more than a few minutes (literally) and provided very inconsistent readings even when those readings were of the same seawater sample and taken only minutes apart. I calibrated it each and every time and had to adjust the calibration 99 out of 100 times. The VEE GEE STX-3 is about twice the price of the Red Sea (and others in it's class) but in my humble opinion worth every penny. If you can't trust the data the instrument provides, what good is it?

My 10+ year old refractometer started giving consitantly erratic readings. It was time to replace it, and I chose this one based on reviews. I was not disappointed. I can feel the quality, just by picking it up. It doesn't feel "hollow". I can see the performance in rock-solid, consistant readings. I did have to calibrate it, though. According to my new bottle of calibration fluid, it was off by .0001. I haven't had to adjust it since then. A bit pricey, but like anything marine-wise... you get what you pay for. Highly recommended!!!

I bought this refractometer because I got tired of constantly going through other cheep ones.For the first few test it was working perfectly. Everytime I tested it with the calibration solution it was always at 35ppt. Just recently it was below 35ppt so I recalibrate it with the calibratio solution. Just out of curiosity I tested it again after its first test and this time it was off by 1ppt. As soon as I recalibrate it it was thrown off again. Now I have to test it each time I have to do a test throughout the day which is very tedious. For the price that I've paid I expected it to work great and last more than 2 months.

I am a Salt Water Aquarium Hobbyist and a refractometer needs to be your best friend. I originally ordered a cheeper one that would never keep a calibration. This unit is amazing. It came calibrated perfectly. It’s heavy and you can tell it’s made well. The numbers are easy to read and are in large print. It comes with a little bag a screwdriver and a pipet for testing. Easy to use if you know what you’re looking at. Highly recommend even though it’s expensive. As they say buy once cry once.

The device seems to work well and seems to be well made. However, the bag that they send the device in is very poor quality - the zippers seem to be 3D printed without sintering, making them extremely weak. Both zipper tangs broke on the very first use.

This Refractometer holds calibration about as well as any other cheap refractometer on the market. Every time you put it down you have to check the calibration. On top of that, the design of it for calibration is not very good if you have to keep calibrating it. The ring is very tight and when you screw the screw down tight, it makes the calibration jump. Returned for a refund to by another brand.

It came in already dialed in perfectly and has seen it’s use multiple times a week since I have gotten it. I had double checked my readings against a spinner, and against an old hydrometer and it is spot on. Absolutely could not ask for a better tool in the saltwater aquarium hobby. Comes with a nice pouch and an eye dropper too! Do not forget to clean it after each use!