Fritz 35PPT Calibration Fluid 37ml

Accurate Refractometer Calibration for Saltwater Aquariums

The Fritz 35PPT Calibration Fluid is a pre-measured reference solution designed to ensure your refractometer provides accurate salinity readings. Proper calibration is critical for marine aquariums, where stable salinity levels are essential for the health of corals, fish, and invertebrates.

With just 2–3 drops, this solution allows you to calibrate your instrument precisely to 35 ppt (1.0264 sg)—the standard salinity of natural seawater. Unlike DIY methods or unreliable tools, this ready-to-use fluid delivers consistent, laboratory-grade accuracy.

Key Benefits

• Provides accurate calibration at 35 ppt (1.0264 sg)

• Compatible with all density measurement instruments and refractometers

• Pre-measured solution—no mixing or equipment required

• Simple 2–3 drop application for quick calibration

• Essential for maintaining stable salinity in reef aquariums

Directions & Dosage

1. Shake bottle well before use.

2. Ensure refractometer prism is clean and dry (rinse with RO/DI or distilled water if needed).

3. Apply 2–3 drops of calibration fluid onto the prism surface and close the cover.

4. Adjust refractometer to read:

   • 35 ppt

   • 1.0264 Specific Gravity

   • 1.3394 Refractive Index

   • 53 mS/cm at 25°C

5. If using an ATC refractometer, allow 45 seconds before reading.

6. Clean prism thoroughly after use.

Recommended frequency: Calibrate at least once per month. Do not return used solution to the bottle. Always seal tightly to prevent evaporation.