swing arm vs floating hydrometer

[Mark3]

I have a old (20+ years) Coralife, deep six that I wondered about its accuracy. So I purchased the Tropic Marin High precision hydrometer.
Photo finish results.....

 

[Mark3]

And just for fun...looked at the refractometer too....needs calibration

 

[Little c big D]

I use the tropic marin high precision hydrometer. I like it, I like it more now that I've seen you test it against other methods lol.

 

[Mark3]

I use the tropic marin high precision hydrometer. I like it, I like it more now that I've seen you test it against other methods lol.

What surprised me was how close my old swing arm was to this...I would call it dead on.

 

[Little c big D]

What surprised me was how close my old swing arm was to this...I would call it dead on.

It's the lack of moving parts that allows for reliability. It's a simple tool and outside of dropping and breaking it, the only thing that can really cause issue is salt build up sticking it.