Ideal temp. and SG for reef.

[SaltyMember]

I have been reading alot regarding temperature adjusting when testing for specific gravity.  But I am getting some confusing information.  One source suggests that with a temp of between 78-80 degrees F that SG readings should be kept between 1.023 and 1.0235.....while another suggests that at 78 degrees F readings should be at 1.025.   I am using a Deep Six Hydrometer (yes, I know it is not as good as a refractomer) if that helps.  Can someone tell me the ideal range to keep my SG at at both 78 and 80 degrees that would be good for corals/inverts?  Any help greatly appreciated.

[mattdog]

I think that you are right on with th 78-80 deg and 1.023 for S.G.  Some people keep it higher or lower.  Whatever floats your boat man.  Mine is at 80 degrees and 1.023.

 

HTH,

 

  Matt

[SaltyMember]

Thanks for your response.  But is the 1.023 measurement what I am actually seeing on my hydrometer?  In the Conscientious Marine Aquarist it says in an example that because most hydrometers are calibrated at 60 degrees that to maintain a SG of 1.025 in your tank at 80 degrees, that you would actually be reading 1.023 on the hydrometer.  I think that is what is confusing me.  When you say you keep yours at 1.023 at 80 degrees, is that a hydrometer reading or some conversion.....

[Nishant3789]

what about floating hydrometers? do they need to be calibrated to the temp?

nishant

[mattdog]

That's my actual hydrometer reading.  I think that book is talking about a scientific hydrometer and not one created for marine tank use.  My hydrometer said on the box that it was calibrated at 78-80 degrees.  You just gotta make sure that you wash them out after you use them and that they don't take hard bumps so that you know that the readings are accurate.  Also, it wouldn't hurt to have someone else check it with a different hydrometer to make sure that your's was accurate.

 

HTH,

 

  Matt

[Satchmo]

I read that same thing and it didn't make sense.  Why are they calibrating hydrometers at 60 degrees, when they're being used in tropical water?  When I look at my reading, should I take it at face value, or adjust for this somehow?

 

EDIT: Oh, thanks MD, you just answered that.

 

(Edited by Satchmo at 7:33 pm on June 2, 2002)

[SaltyMember]

You may be right Mattdog....I don't know if he was talking about a swing arm hydrometer.  Here is one of the articles I was talking about....check the SG table and the info regarding keeping SP at 35ppt.

 

http://www.animalnetwork.com/fish2/aqfm/19...s/1/default.asp