Target Salinity Calculator

Target Salinity Calculator

Enter pond volume + current salinity (ppt) + target salinity (ppt). This calculates how many pounds of salt you need.

Salinity Reference (ppt vs % + real-world notes)
This calculator uses ppt (parts per thousand). Some meters show percent (%). Conversion: 1.0 ppt = 0.10%.
ppt % What this level usually means
0.3 ppt 0.03% Light “background” salt (common)
0.6 ppt 0.06% Moderate support / often used temporarily
1.0 ppt 0.10% Common “support” level in freshwater systems (species-dependent)
2.0 ppt 0.20% Where many pond/wetland plants start to struggle (varies a lot)
3.0 ppt 0.30% Common lower end of “salt-as-treatment” ranges for parasite pressure
5.0 ppt 0.50% High—more likely to damage plants; used as treatment by some keepers
Plants: In controlled plant testing, many species show reduced quality around 2–4 ppt, and at 5–6 ppt a lot of species can lose about half biomass/quality. (Your exact plants may be tougher or weaker.)
Nitrite protection rule-of-thumb: add 0.002% salinity per 1 ppm nitrite (that equals 0.02 ppt per 1 ppm nitrite). Example: 5 ppm nitrite → +0.10 ppt.
Enter values and click “Calculate Salt Needed”.

Note: This is dosing math. Pond conditions vary (plants, parasites, temperature, time at level, etc.).