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Grue
12-28-2007, 01:20 AM
As I am New to all of this I hope you don't mind a stupid question. The Specitic gravity of water should be? I am getting conflicting answers. Around the net I see figures that range for ocean water of 1.024 to 1.026 I went to my LFS and bought a quart for testing.(Fresh natural sea water) I used my instant ocean tester found water tested to 1.025 So today I took a trip to the ocean (Halfmoon bay califorina) And Silly me tested the ocean =p Again using the same tester the water came out to 1.025 This confuses me. On the bags of instant ocean It says to mix to 1.020 to 1.024 which I would think is low. I also looked at alot of the other salts in my LFS they all say the same mix to 1.020 to 1.024 WHY? This is killing my brain. I do realise that we are talking .001 to .002 differance but I would think it would make a difference to the corals. At the max for sea water of 1.026 to 1.027 would give about 36ppt salinity. Will that burn things? One confused newbie :confused:
Grue

dakar
12-28-2007, 09:44 AM
The general rule of thumb is a specific gravity of 1.024-1.026. So the research you have done has not been in vain. Salinity varies all over the world. IMO the key to keeping things happy and healthy is to maintain a constant and stable environment for them to live. They are already being removed from their habitat, but will adjust and be accustomed to slight differences.

SG can also be measured in PPT (parts per thousand) so the differences can be pretty dramatic.

Hope this helps.

melev
12-28-2007, 02:13 PM
The salt being sold in stores is more often used for fish tanks, not reef tanks. So it is marked for those people that have a predatory fish only system, with lion fish, groupers, puffers, etc. Those tanks tend to run at 1.021 sg.

Reef tanks run at 1.026 sg / 35ppt - that is what corals are used to and thus we try to match it. So rather that worry about the label on the bag or bucket, mix it up to what your livestock needs. Start out by mixing 1/2 cup salt per gallon of water, and add a little more if necessary.

This article should help:
http://reefkeeping.com/issues/2007-11/nftt/index.php

Grue
12-29-2007, 12:00 PM
WOOT, Thank you!!! Locks 1.026 in to da brain
Grue