Can marine fish survive in 1.035 water?

  • We are currently upgrading MFK. thanks! -neo
Many fish can withstand parameters that seem extreme as long as it happens slowly.
That said, I would test the refractometer with some water of a know Sg and calibrate.
If you have some distilled water you can clean the slide and calibrate to 0 ,
then retest.
Be sure to clean the lens and slide after use because salt can accumulate and throw off test results.
 
Ditto BIG-G BIG-G . While all looks fine now the physical stress on the fish of having that much higher of a salt concentration could lead to problems.
 
It depends on the fish. There are some that can tolerate extremes of salinity:

 
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