How to use a hand held refractometer to measure salinity.

This tutorial, as part of my student training in basic seawater carbonate chemistry tutorial series, is a learning tool for students wanting to learn how to use new equipment. This video covers the use of a hand held refractometer which can be used to measure salinity in liquids such as seawater. Calibration and basic information on care are also covered.

[@shaanhajju3368]

Thank you! That video was straight to the point and exactly what I was looking for. I learned something valuable from it.

[@suellenlines6766]

Thank you for this video. This is exactly what I was looking for, before purchasing one

[@coleensuckling5276]

Glad it was helpful!

[@andrewsmythe8763]

Very good explanation for novices like me, thanks!

[@tom496]

Excellent video! Thank you. A little frustrating that I can't quite read what's written on the back of your left hand. Also, wondering what happens to the naughty lab users who don't properly rinse the saltwater from their refractometers. Thank you again for an excellent video.

[@RajA-gx5ur]

Good demonstration! Thankyou 😅

[@Anichthyophile]

Excellent video ma'am

[@jameswilliford5478]

Distilled water will get you close, but you will get more accurate results using a 35 ppt calibration solution. I calibrated with the distilled water then tested my reef tank water and it showed 35 ppt. Then I recalibrated using the 35 ppt calibration solution and tested my water again and it was at 31 ppt.

[@coleensuckling5276]

Hi James, I agree with you, but if you're on limited budgets freshwater is a good medium to use as long as you use it consistently and appreciate its limitations. In the past we have compared the performance of the handheld refractometer to conductivity meters which are used for open water measurements and unsurprisingly the hand held is not as good, reliable or consistent in measurements. But as I say, we work with what we have and within our budgets as long as we appreciate the limitations. Thanks for your input!

[@jameswilliford5478]

Very true. I was stuck with a hydrometer for years.

[@GRBtutorials]

Or use a precision scale (you can buy one for $10) and make your own calibration solution.

[@mvhemp]

Question as I'm considering this model as opposed to the plastic hydrometer that at some point stop reading correctly... I keep seeing videos where people use RODI water to clean the refractometer. Is that necessary to wipe it clean? I know the refractometer solution at 35 ppt is recommended for calibration but this "RODI" water, is that necessary for cleaning the refractometer or could i just use sink water or even purified water??

[@diane-mn8ou]

Very nice presentation

[@wilfredogonzaga602]

Hi ,can I use this Refractometer in fish processing project ,i.e sardines and the like.thanks I bought one to measure the salinity level of the finished products being processed.thanks and more power😊😊😊

[@RaySarasin]

I use mine to test the water in my honey it must be around 18% water before I pull it of the hive

[@tombowers2020]

Always trust a lab tech with notes written in ink on their hand.

[@james9848]

Can I use for my fish aquarium this same stuff to check the salt in 💧 water.pls reply.

[@coleensuckling5276]

Yes you can

[@devananthr3176]

Can we measure the salinity of sea water with this ?

[@coleensuckling5276]

With some models you can, with other you cannot. If purchasing one, make sure it covers the salinity range you expect to operate across. I tend to purchase ones that have a 0-100 ppt range.

[@solaimankhan1191]

Price please

[@jhonatanperez4118]

I dint like your video because you dint show the saltwater test

[@coleensuckling5276]

Thanks for the feedback, I'll keep this in mind for future videos.