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Previous Water Parameters

When keeping an aquarium, the best husbandry requires owning and using test kits to measure water parameters.  Most kits have enough tests to last a full year, and using these kits frequently assures happy livestock.  If a kit has 50 tests, that's an indicator it should be used weekly.  I'd recommend that kits be replaced annually.  Mark the date on the box when you purchase it and open it for the first time to avoid relying on a dated kit.  Older reagents may lead to false readings. Please read my full article here:

Test Type Recommended Parameters matching Natural Sea Water (NSW)
Salinity 1.026 sg - a calibrated refractometer is the best tool to measure salinity. A hydrometer will measure specific gravity, while a refractometer will show parts per million. 35ppt is the target measurement that is closely equal to 1.026 sg.
pH 7.9 to 8.3 - this varies daily in a tank; measure with a Pinpoint Meter or controller rather than a test kit.
Temperature 78° F to 84° F - average reef temperature tends to be 81° F; try to keep within a 1.5° to 2° swing at the most.
Alkalinity 8 to 11 dKH -or-  2.86 to 3.89 meq/L
Calcium 390 to 450 ppm
Magnesium 1350 - 1400 ppm (or 3x Calcium levels)
Phosphate .03 ppm - leading cause of nuisance algae in your tank: click for article
Ammonia 0 - anything higher is toxic
Nitrite 0 - anything higher is toxic
Nitrate 10 ppm or less - huge water changes bring down nitrates: click for article


In February 2011, my new 400g reef was started. Readings are taken at various times, and are documented here to allow you to see how the parameters vary over time.



Readings from my 280g reef were taken at various times, and are documented here to allow you to see how the parameters vary over time. This aquarium ran for nearly six years, but in early July 2010 it sprung a leak. Any measurements thereafter were taken from the livestock vats while the new system was being built from the ground up.




2007 - 2006

2005 - 2004


* Both reef tanks were upgraded to a 280g during this year.




Blank entries were not taken for whatever reason. Certain tests are ignored, such as Ammonia because they typically result in 0.

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