Salt Mix Calculator
Calculate salt mix additions and salinity adjustments.
This tool estimates how much dry salt mix to add (or how much saltwater to replace with fresh RO/DI) to move from your current salinity to your target salinity. It supports PPT or Specific Gravity (SG).
How this is calculated:
- Volume conversion: gallons → liters (× 3.78541)
- Salinity delta from current to target
- If increasing salinity: liters × ppt rise × (salt strength ÷ 35). Most reef salts need 36 to 39 g per liter for 35 ppt; check your bag. 37 is a safe default.
- If decreasing salinity: estimated amount of tank saltwater to replace with RO/DI
- SG conversion uses reef-range approximation:
SG ≈ 1 + (ppt × 0.000754)
