Ok so... I've had my tank going for 1 week now and so far so good until I used 2 Hydrometers +/-0.003 (Instant Ocean) and a refractometer +/-0.006 (Calibrated with RODI water) and all 3 are giving me a different Specific Gravity readings. I am nervous that I either have too much or too little salinity. Any suggestions and help would be great as far as what to do and which piece of equipment i should use? Thx in advanced