salinity question

[sphelps]

Originally Posted by fishytime

Um, don't you mean distilled water Steve?...... I wouldnt callibrate a refractometer with RO....but that's just me I guess

Wouldn't bother myself, if you want to go through that much trouble it's up to you but I put money on it not making a difference. Pretty much everyone has RO water on hand and realistically you're interested in the change of salinity from your source water and mixed saltwater plus if you're off by a tenth of a percent it won't mater, acceptable salinity is pretty big range, consistency is more important. My tank does just fine using a refractometer calibrated with RO.