I don't test O2 at home but every once in a while I'll bring a sample into one of the LFS and have them test for me. Unless you water is really stagnant it should not be something you need to worry about testing to often.
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- Greg
90G : Light - Tek 6xT5 | Skim - EuroReef RS135 | Flow - 2xVortech MP40W | Control - Reef Keeper 2
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