- Sku: R21485
- Vendor: Red Sea
Red Sea Magnesium Test Kit
The Red Sea Magnesium Test Kit measures magnesium in your reef or marine aquarium so you can keep it in the ideal range. Magnesium holds calcium and alkalinity stable, which is the foundation of healthy coral growth and a trouble-free dosing routine, so an accurate reading takes the guesswork out of balancing your tank. This colorimetric titration kit uses three reagents for a clear, repeatable endpoint and includes enough for roughly 75 tests. Browse the rest of our aquarium test kits to round out your testing station.
Features
- Measures magnesium (Mg) in marine and reef aquariums
- Colorimetric titration with three reagents for a clear endpoint
- Roughly 75 tests per kit
- Helps you keep calcium and alkalinity stable for steady coral growth
- Trusted Red Sea reagent quality and accuracy
Specifications
| Measures | Magnesium (Mg) |
| Method | Colorimetric titration, three reagents |
| Tests per kit | Approximately 75 |
| Recommended range | 1250 to 1350 ppm |
| Water Type | Marine and reef |
| Brand | Red Sea |
Recommended Pairings
- Red Sea Reef Foundation C Magnesium (liquid) to raise a low reading
- Red Sea Foundation C Magnesium Powder for economical dosing
- More aquarium test kits
- Salt water supplies
FAQ
What is the ideal magnesium level? Most reef tanks run best between 1250 and 1350 ppm.
Why does magnesium matter? It keeps calcium and alkalinity in solution. Without enough magnesium those two precipitate out and your dosing stops working.
How many tests are in the kit? Roughly 75, using the included Mg-A, Mg-B, and Mg-C reagents.
Can I use it in freshwater? No. Magnesium testing is a marine and reef parameter, so this kit is for salt water.
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Red Sea Magnesium Test Kit


