Salinity Adjustment Calculator
Estimate water replacement needed to move specific gravity toward a target.
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What this tool does
Estimate water replacement needed to move specific gravity toward a target. Constant-temperature, linear specific-gravity mixing approximation. Make gradual adjustments and re-measure.
How to use the Salinity Adjustment Calculator
- Enter or select system volume in gal.
- Enter or select current specific gravity.
- Enter or select target specific gravity.
- Enter or select replacement specific gravity.
- Read the calculated result; change any measurement to compare alternatives.
Formula
replace fraction=(current−target)/(current−replacement); replacement volume=system volume×fraction (linear SG approximation)
- volume
- System volume (gal, before metric conversion)
- current
- Current specific gravity
- target
- Target specific gravity
- replacement
- Replacement specific gravity
Constant-temperature, linear specific-gravity mixing approximation. Make gradual adjustments and re-measure.
Worked example
For salinity adjustment calculator, the following measurements illustrate the exact method: System volume: 75; Current specific gravity: 1.028; Target specific gravity: 1.026; Replacement specific gravity: 1.
Inputs
- System volume75 gal
- Current specific gravity1.028
- Target specific gravity1.026
- Replacement specific gravity1
Result
- Water to remove and replace5.36 gal
- Fraction of system (%)7.14
Results explained
- Water to remove and replace
- Water to remove and replace from the formula above, expressed in gal before metric conversion. Constant-temperature, linear specific-gravity mixing approximation. Make gradual adjustments and re-measure.
- Fraction of system (%)
- Fraction of system (%) from the formula above. Constant-temperature, linear specific-gravity mixing approximation. Make gradual adjustments and re-measure.
Frequently asked questions
replace fraction=(current−target)/(current−replacement); replacement volume=system volume×fraction (linear SG approximation)
No. Individual animals differ. Consult your veterinarian before changing feeding or treatment, and seek immediate veterinary care for poisoning concerns.
Constant-temperature, linear specific-gravity mixing approximation. Make gradual adjustments and re-measure.
Use current measured weight, actual food or product label values, and the dates or water readings requested. Check units before entering any value.
Verify if the animal is ill, pregnant, growing unusually, or on a special diet. Aquarium chemistry changes should be measured gradually and checked against product instructions.