Such a big difference between hydrometer and refractometer!

MrRoo

In Memoriam
My salinity was around 1.021 and I was told by some of the people on here to get it up around 1.025-1.026 so I did. Well I purchased a refractometer and tested it and it was 1.030! I calibrated it again and got the same results. I am using RO water since I could not find the mixture and need to order it.
 

drparker

Premium Member
Don't do any drastic changes. Get the mix and then re-test. Mine showed 1.029 but after using the fluid was really right on at 1.0265
 

sjm817

On Yer left!
Premium Member
Dont assume either is accurate until you calibrate with a 35ppt solution.
 

MrRoo

In Memoriam
I was not going to change anything, just topped the tank normally with RO water. I do not mix my own salt I buy Catalina Water.
 

seapug

Premium Member
Catalina water is usually around 1.027-030. That's the typical salinity where it's collected. It's not necessarily a bad thing.
 
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