Who keeps backup calibration fluid?

[boun11]

I am learning a very hard lesson today. I noticed that some of my LPS are receding and lost all but one blasto colony. I tested my Alk and it was a bit high but I brought that down but that did not stop the receding. I lost a few chalice frags and some of the more sensitive sps RTN on me. I tested the salinity and it was at 1.026 so I thought it was fine but then I remember Ian told me that my refractometer is off when he borrowed mine but then I used the calibration fluid to calibrate it and I thought it was fine. Again, it just didn't add up so I went over to Jim today (Green Marine) to test my refractometer with his calibration fluid and sure enough it was off by .03 Instead of reading 1.026 it was reading at 1.023. I had that calibration fluid for over 3 years and I guess I must have not close it tight enough.

I brought the salinity down slowly and I hope this solve my LPS problem. So.. in short, I am buying two of the calibration fluid just in case I need to double check the level.

Anyone keeps backup?

 

[seminolecpa]

I have about 60 bottles .

 

[bookfish]

I have about 60 bottles .

I guess it's the opening and closing of the bottle (and the evap that causes) over months of use that screws up the standards. On BRS the bottles of 35ppt standard are only $7 instead of $9 or $10 at MD.