Specific Gravity

[spetitti]

Hi-
I have just set up a small 12 gal salt water tank. Nothing in it but live sand and a medium size live rock. Of course I'm anxious to get some fish into the tank but the problem is my SG, I don't trust it. I check it 3 times, one right after the other and every time I get a different result. First one is always 1.030, second and third 1.024. Does anybody have an answer and a solution to this problem I would deeply appreciate one. Even though the rock looks nice with the sand I would love to add some fish with a clean conscious.
Thanks for any help
Spetitti

 

[James77]

what are you measuring with?

 

[Psychojam]

First off, if you are using a hydrometer, you have to season it by filling it with saltwater and letting it sit overnight.

Second, make sure that the tank has cycled with the live rock before adding fish. IMO, you shouldn't cycle a tank with a fish. It's not necessary and some would argue cruel to the fish.

Lastly, hydrometers arn't that accurate. Sometimes bubbles can increase the bouyancy of the swing arm. Also, they don't correct for temperature. and furthermore, if you don't rinse them out with freshwater when you're don, salt can accumulate and screw up your next reading. You're better off with a refractometer if you want more reliable SG readings

Good Luck

 

[bertoni]

[welcome]

I've had better luck with refractometers and conductivity meters than hydrometers, but all SG devices should be checked for calibration:

http://www.reefkeeping.com/issues/2004-06/rhf/index.php