Vertex Refractometer Q

[blk822822]

I just bought a Vertex Refractometer and tested my water . It was at 1.030. Then I used my plastic lever style teseter and it shows 1.021, I have been mixing my water with it to 1.025 for a while now. I fallowed the calibration test for the vertex tester with ro water and it read 1.001. Should I beleive the refractometer over the cheap plastic one, and I think I know the answer to this question.

And if its right how fast should I lower the salinity of my tank? and do I do it with just RO water or do water changes with a low salinity mix? Help please..

O, and the only thing I see wrong with my corals or fish is not hardly any polyp extension from my SPS'.

 

[NWDiver]

You should see if you can borrow some pinpoint 53 mS calibration solution and do the calibration with that at ~68deg F. be sure to let the water sit for a few minutes to match temp. Does the refract say ATC on it?
I am going to Barrier tomorrow if you want to get some pinpoint from me, I don't know if they stock it. I wouldn't change anything until you are sure there is a problem.

 

[blk822822]

Does not say ATC anywhere. just Vertex Refractometer model VT-R-HHRR A

I was thinking about going there tomarrow , maybe they could use it to test there water and see if it matches there equipment. Not sure if I can make it there tomarrow, but really want to.

 

[NWDiver]

It would be a really good idea to bring the refractometer and some of your water.
ATC= automatic temperature compensation (I think)
If your vertex is not, you have to do the temperature correction yourself.
I just got a bad refractometer from BRS. Boomer helped me sort it out last week.
Mine read 1.030 when calibrated correctly, and my new one read 1.026.
The thread is in chemistry if you are interested.

 

[blk822822]

The destructions say to put the sample on and wait for the water temp to adjust. What ever that means.The top of the chart in the eye peice says 20degrees C on the top.

 

[blk822822]

So if I read this right I need to place the sample on and wait for it to get to 68 degress and then check it. If so, then it still reads 1.030

 

[NWDiver]

I think you should get a second opinion
They can be skewed if you don't calibrate in the seawater range. some are worse than others.
Have the LFS check for you, or I'm happy to help if you want to meet tomorrow.
-Todd

 

[barrierreefcf]

We have the proper calibration fluid in stock. Bring it by and we'd be happy to calibrate it and compare against ours.

 

[blk822822]

Thanks to the great people at barrier reef my refractometer is calibrated. And my tank isn't as bad as I though , it's at 1.026. Thanks to Brie for the fix.