refractometer

Pickup in Kitchener Ecotech MP40w (x2) $300 each (Not quiet drive) Ecotech MP10w $180 (Not quiet drive, Needs new wet side) Vertex Omega 150 Protein Skimmer $150 Hang on Back Protein Skimmers (x2) $40 each (Missing pumps) In Tank mini Skimmer (Fits in back of Biocube) with pump $40 Jebao...

Are you properly calibrating your refractometer? Lot of people just use RO/DI water which will read 0..however your not going to get the the most accurate results. the next batch of people will use proper 35ppt/1.026 calibration solution which gets you closer.. but ar you taking into account...