Refractometer

[hawaiiguy]

I'd say e-bay... Locally I wasn't able to find one for under 60$. On e-bay you can get one easily for 30$ or under in US dollars. Generally after exchange and shipping it'll end up being 40-50$ CAN but that's still cheaper than buying locally. Just make sure that if you get one off e-bay you're sure it measures salinity (in PPT and/or SG). The first one I got measured on the brix scale which is a measure of dissolved sugar. I was able to return it no prob though.