[SNIP]
If the corals and fish look healthy I don't see the need for such high
accuracy.
In other words, close enough.

Chris

The difference between my two hydrometers was so huge that who knows
where "close enough" is? Maybe the fish LOOK healthy to me, but would
live a lot longer if the salinity was correct.

Besides, I like ACCURACY. "Close enough" doesn't do it for me.