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08/13/2018, 02:06 AM | #26 | |
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Location: Sydney Australia
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08/13/2018, 11:18 AM | #27 |
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Location: Dewitt MI
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Calibrating with RO/DI water can cause some variation at 35 ppt. Also, how do you now the RO/DI water is actually 0? I have a storage barrel for my ATO and the water going in is zero TDS but if I take out a sample it will register above zero as the contaminants will get into the barrel.
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Gary 180 gallon, 40 gallon sump, 3 250 W MH + 4 80W ATI T5's, MTC MVX 36 Skimmer, Apex controller Aquamaxx T-3 CaRx Current Tank Info: A 2 Barred Rabbitfish, Red Head Salon, Yellow/Purple, McMaster Fairy, Possum, 2 Leopard Wrasses, Kole, & Atlantic Blue Tangs, 2 Percula Clown, 3 PJ and 1 Banggai Cardinalfish , Swallowtail, Bellus and Coral Beauty Angels |
08/13/2018, 11:59 AM | #28 | |
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Location: New Brunswick, Canada
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My specific refractometer was designed with the intention of being calibrated at 0 ppm with RODI water. While I know there can be some fluctuations with not 'pure' RODI, I'm fairly sure the 1-2 PPM that it picks up contaminants with in my barrel isn't going to swing it too far considering that the PPM of saltwater is something like between 10,000 and 30,000. Most hobbyists aren't wielding scientific instruments with precise tolerances. Any fluctuations I'm going to have from using RODI water stored in a barrel are likely within the tolerances of the refractometer itself. As for any adjustments to the curve, I'd agree with you. It would be better to calibrate with 1,026, you would get your most accurate reading if that was the case. What I do is calibrate to RODI, check what my tank reads, and match my water change to that, so even if it is 'off' from 1.026, its at least the same going in as it is going out. I have twice checked my refractometer in the 8 months I've had it against a 1.026 solution (Local reefer has it) and both times I did my calibration with my RODI water was bang on accurate at 1.026. So while not ideal, its close enough to have not caused me any issues! |
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08/13/2018, 12:45 PM | #29 | |
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Location: Dewitt MI
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Gary 180 gallon, 40 gallon sump, 3 250 W MH + 4 80W ATI T5's, MTC MVX 36 Skimmer, Apex controller Aquamaxx T-3 CaRx Current Tank Info: A 2 Barred Rabbitfish, Red Head Salon, Yellow/Purple, McMaster Fairy, Possum, 2 Leopard Wrasses, Kole, & Atlantic Blue Tangs, 2 Percula Clown, 3 PJ and 1 Banggai Cardinalfish , Swallowtail, Bellus and Coral Beauty Angels |
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