calibrating refractometer

[art13]

Don't use ro/di for this, get the solution. For 6 months i couldn't figure out why my coral were slowly dying, found out my reading was 1.022. I also calibrate it before every use, as it does wonder from time to time.

 

[njtiger24 aquariums]

Don't use ro/di for this, get the solution. For 6 months i couldn't figure out why my coral were slowly dying, found out my reading was 1.022. I also calibrate it before every use, as it does wonder from time to time.

Just ordered some solution. I used RO/di to calibrate mine; now lucky I have not seen any issues that I am aware of.

 

[Sunny]

1.022 is not in any ways low for corals to die. I use RO water for calibration and have done that for years. As a matter of fact most store do not keep their salinity at more than 1.020 no matter what they claim they do.

If corals are dying with 1.022 there is something else wrong that you need to look into.

 

[redfishbluefish]

I fully agree that 1.o22 isn't going to kill corals.

However, I am rather adamant that calibration solution should be used to calibrate your refractometer. Otherwise, I suggest going back and using a swing-arm hydrometer to measure salinity....about equal to a refractometer calibrated with RO/DI!!!!!

Don't feel that there is a need to go out and spend the 8 to 12 dollars for that calibration solution. Here's the poorman's way of doing it. Go to a local reefer's home who uses a calibrated refractometer. Measure his tank water with that refractometer, taking note of the reading. When your friend is not looking, steal a small bottle's worth of water from his tank (and store it in a sealed bottle). You now have calibration solution with a known refractometer reading. And it didn't cost you anything. Say goodbye to your friend with a smile on your face.

 

[art13]

I might be on the other side of the fence with the 1.022 reading. I used ro/di and for months, i couldn't figure out why my coral were slowly dying, mostly sps, but the lps were by no means taking off. I would put a frag in, it would take about 3 months for it to stn. All parameters in range, and one day i ordered some solution and found out i was at the 1.021-1.022 reading. i put the salinity back where it should be and after that no more 3 month stn on my sps or stagnant growth on lps.

 

[redfishbluefish]

@art13 , I'm not sure what you do to maintain alk and calc, but by "fixing" your salinity, you also raised up you alk, calc and mag numbers. That is a possibility of why you saw improvement. I don't think it was the salinity alone.

 

[art13]

I was dosing alk and calc to keep those numbers at the time, they were always good.

 

[slimfitz]

Your fine, mine slipped down to 1.018 over time due to my refractometer not being calibrated. My corals didnt die but they def stopped growing. I bought one of those Milwaukee refractometers after that.