Hydrometer
From The Aquarium Wiki
A hydrometer is a device used to measure the specific gravity (sg) of water.
It is commonly used to measure the amount of salt in a body of water when setting up brackish or saltwater tanks. You'll want a hydrometer with a specific gravity scale of at least 1.005 to 1.030, salinity of 5 to 40.
Cheaper passive hydrometers are designed to be used at their calibrated temperature. Usually 25°C (77°F) . If you measure at different temperatures you'll have minor errors.
- For more accurate devices, see - Refractometer.
Corrections[edit]
| °F/°C | Adjust |
| 4.4°C (40°F) | -0.002 |
| 10°C (50°F) | -0.001 |
| 15.6°C (60°F) | -0.000 |
| 21.1°C (70°F) | +0.001 |
| 26.7°C (80°F) | +0.002 |
| 32.2°C (90°F) | +0.004 |
| 37.8°C (100°F) | +0.005 |
Links[edit]
- Hydrometer Temperature Corrections
- Hydrometer on Wikipedia
