What alkalinity level do you keep in your REEF?

[Myka]

Please do not vote if your tank is not a reef.

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I have found it very interesting to watch "the" reef tanks of the time over the years. Something I have noticed is 10 years ago, even up to 3 years ago Salifert test kits were "industry standard" for most of the leading reef keepers, they still are for many people. During this time, the leading reef keepers have found that keeping an alkalinity level of 9-10 dKH has given them the best results.

In the last 3 or so years Elos kits have begun to move in as the NEW (oh la la lol) "industry standard" for many leading reef keepers. People are also starting use devices like colorimeters, and more accurate test kits like Hanna, LaMotte, Hach. Many of today's leading reef keepers are beginning to suggest (and keep) lower alkalinity levels of 7-8 dKH which makes a lot of sense since NSW is close to 7 dKH.

Interestingly enough, many people are noticing that these more accurate means of testing are often reading 2 dKH lower than a Salifert test kit. I have both Salifert and Elos alkalinity test kits (both new), and I have also compared them to a Hanna Colorimeter. When I tested the same sample of my tank's water I got:

Hanna Colormeter = 7 dKH (converted from 125 mg/l)
Elos = ~7 dKH (Elos goes up in 1 dKH increments, it was pretty close to 7, as it barely changed)
Salifert = 9.15 dKH

Anyway, this is all just something that I have noticed over the years be reading tank logs, journal type books (old and new), etc. Recently, I have also heard other people talking about this. By no means is this some sort of published data. Well maybe, but I don't know where it would be.

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So long story short, I am interested to see some more evidence. So, what test kit do you use, and what level do you keep your alkalinity at?

If you have two kits, and have tested the same sample of water with both, you can vote twice. I forgot to. *smacks forehead*