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carol stringer
05-24-2010, 05:15 PM
Hi, still getting used to using this site.
What do you mean by gravity I know about alkanity.
The room stays about the same temp. Is it better to mix our own reef salt to the water we get from the marine centres.


05-24-2010, 10:29 PM
'Specific Gravity' (SG) can be said to be the density of water and in regards to salt water samples means the salinity level of your aquarium water and is measured using a refractometer or hydrometer (for example 1.023 or 1.027 SG).