- API = 440ppm
- Red Sea = 430ppm
- Hanna = 479ppm
The good news is that I have been getting consistent test results in all three brands. Now what does this mean, is one kit better than the other? No, and here's why..
Consistency is what you want from these test kit. All test kits will have some sort of +/- for precision. As long as you can make adjustments based off of the same test kits, thats all that really matters. Do I care if my Calcium is 440ppm or 479ppm from the Hanna Checker? Not really, because if I can maintain stability and keep those numbers close from week to week, I'll be a happy camper and so will my corals.
Corals can survive and thrive in all types of water conditions. The goal here is stability.
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| Hanna Calcium Checker (Left), Red Sea Calcium Pro (Center), API Calcium (Right) |
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| Hanna Calcium Checker = 479ppm. Use RO/DI water, add reagent A, mix and get base reading. Add drop of tank water, and reagent B powder, mix and get final result. |
The API, Red Sea, and Hanna Alkalinity test results coming soon, stay tuned!



