How do I get my prefered SG and temp using the Milwaukee Ref.?

[Style68]

Hello Guys,

First I would like to apologize if this question was posted already, but I could not find an answer to my noob question regarding using a Milwaukee MA887 Refractometer to get the desired SG for my tank.

I calibrated my refractometer to 1.000SG / 0ppt using distilled water while keeping the room temperature at 79f. I also used the 1.025 solution that came with the unit to verify it is reading correctly. I get a reading of 1.025SG / 34ppt at any room temperature the unit senses (76f - 79f). Is that where the ATC works it's magic? Is the ATC using 77f degrees as the reference?

If I wanted my tank water to be at 1.026SG at a temperature of 79f how would I go about achieving that if the unit is calibrated for 1.025SG at 77f?

Any help would be greatly appreciated.

 

[Ron Reefman]

The 2 degree difference in temperature makes such a small difference in the reading of SG that I never even consider it. And if your SG is 1.025 or 1.026 or even 1.027, it really doesn't make much difference either. The goal is to keep it stable. SG isn't a parameter that is that important IMHO as it doesn't change much unless you screw up a water change by adding water that is much higher or much lower than that of your tank.

Getting started, ammonia, nitrate and phosphate are the ones you you need to be in control of. And once your tank is cycled the ammonia will zero almost all the time. As your tank matures and you add stoney corals, alkalinity, calcium and magnesium will become the ones you need to control.

 

[Style68]

The 2 degree difference in temperature makes such a small difference in the reading of SG that I never even consider it. And if your SG is 1.025 or 1.026 or even 1.027, it really doesn't make much difference either. The goal is to keep it stable. SG isn't a parameter that is that important IMHO as it doesn't change much unless you screw up a water change by adding water that is much higher or much lower than that of your tank.

Getting started, ammonia, nitrate and phosphate are the ones you you need to be in control of. And once your tank is cycled the ammonia will zero almost all the time. As your tank matures and you add stoney corals, alkalinity, calcium and magnesium will become the ones you need to control.

Thank you Ron. I wonder how others handle this since I have read many forum threads and articles with people who absolutely want 1.026SG at 78-79f.

 

[Ron Reefman]

I just looked up a chart. A difference of 5 or 6 degrees F will raise the SG reading by 0.001. So you want 1.026 at 78-79F? You'll get the same basic reading from about 76 to 81F. Each degree makes about a 0.0001 to a 0.0002 difference. If that's an issue for you, all I can say is 'good luck'.

http://www.algone.com/salinity-and-specific-gravity-guidelines-for-the-saltwater-and-reef-keeper

 

[Style68]

I just looked up a chart. A difference of 5 or 6 degrees F will raise the SG reading by 0.001. So you want 1.026 at 78-79F? You'll get the same basic reading from about 76 to 81F. Each degree makes about a 0.0001 to a 0.0002 difference. If that's an issue for you, all I can say is 'good luck'.

http://www.algone.com/salinity-and-specific-gravity-guidelines-for-the-saltwater-and-reef-keeper

Great! Thanks for your help Ron.

 

[GimpyFin]

Ron is right. I have a milwaukee as well and I get the same reading within about 4 degrees here or there. If your temp is out of that range when testing, just take that into account when reading. I also agree with stability. 1.025, 26, and 27 are all fine.

 

[Style68]

Ron is right. I have a milwaukee as well and I get the same reading within about 4 degrees here or there. If your temp is out of that range when testing, just take that into account when reading. I also agree with stability. 1.025, 26, and 27 are all fine.

Thanks. So if my reading shows 1.027 and 36ppt I am OK.

Thanks

 

[Ron Reefman]

Stability is a good thing, but salinity is one that doesn't fluctuate very much, if at all, unless you do something wrong. And it's also one of the parameters that really isn't that hard on fish, corals or other inverts as long as it's gradual, like due to evaporation or doing a water change with 1.025 water when the tank is 1.027. The net effect isn't going to bother anybody IMHO.

 

[Style68]

Stability is a good thing, but salinity is one that doesn't fluctuate very much, if at all, unless you do something wrong. And it's also one of the parameters that really isn't that hard on fish, corals or other inverts as long as it's gradual, like due to evaporation or doing a water change with 1.025 water when the tank is 1.027. The net effect isn't going to bother anybody IMHO.

Good to know.