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Questions about salinity meters

Apr 17, 2005
hey I'm looking to buy a new tool to measure salinity and I'm a little confused on on what is best. I'm looking at a digi-lab meter or a refractometer. I have no idea what a refractometer is but i was reading they are accurate. I have posted the link of the digi-lab meter. Has anyone had experience with these and what is the most accurate meter?

Thanks a lot,
Ben Matson

I think a refractometer is the best - as accurate as anyone really needs to go. Actually I have heard those digi things are good too, however I'm not sure of the brand of that one, but it does look like the things I've seen.

Sorry my answer isnt the straight one you wanted :biggrin2:
I have used the Seatest Specific Gravity Meter (with the swinging arm) for probably about 20 years. I have several in case I can't find the main one. Not sure how accurate as compared to a digital or the more advanced salinity meters, but other than making sure the airbubbles are off the arm, it's worked fine for me. And the price is quite a bit less expensive compared to the link you provided. I would love to have one of those one day though!

Thanks for the responses. The price is high yes, but i figured if it was accurate it would be worth it. The refractometer I was looking at was cheaper and that might be best.
Refractometers are said to be the most accurate. You can get a good one for $40 to $50 or a really, really good one for more than $100.

The swing arm ones are reported to be VERY variable - one guy over here had problems with his corals dieing - with perfect parameters. After a test with a borrowed refractometer - his salinity was actually 1.033. . The reefers I have contact with here never use them, as many have had bad experiences.

If money is a problem, a floating hydrometer can be accurate, but people generally dont like them as they are easily broken.

The swing arm ones are nice and cheap and hopefully you get a good one - it might pay to have it tested with a refractometer, just to make sure.
Good call. If you can get a swing arm that has been tested, you are probably ok...I use a swing arm for general check ups, and a floating type for checking parameters, but I might be joining the digital age soon.
I got an eBay refractometer for about $30 and it is great... compared it to a $100 odd one and they are the same
Im a big fan of the hydrometers, the ones which float. They are well cheap and as accurate as you really need to be.

A lot of people don't like them because they float around in the tank and you can't g et a good reading but if you fill up the tube they come in then they are perfectly still... I think that if you are on a budget then they are ideal