What water hardness for nerites?

re: pygmy cories and your the salt in your tank.

Per wikipedia "...They can tolerate only a small amount of salt (some species tolerate none at all) and do not inhabit environments with tidal influences." http://en.wikipedia.org/wiki/Corydoras
 
It's interesting, I've almost always kept salt in my tanks, and had cories and loaches...was actually big into a variety of botias...and never had any problems...always had happy active bottom feeders.

OTOH, I didnt usually keep the full recommended amount in there because I had live plants.

Maybe the amount was just 'small' enough.
 
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