water chemistry

Salinity

Total dissolved salt

What does Salinity mean?

Salinity is the concentration of dissolved salts in water, expressed as parts per thousand (ppt) or specific gravity (SG). Reef target: 35 ppt = 1.025-1.026 SG. Brackish: 5-15 ppt.

How is Salinity used in aquariums?

Reef target: 35 ppt = 1.025-1.026 SG. Brackish: 5-15 ppt. Freshwater: 0 ppt. Measure with a refractometer (calibrated monthly with 35 ppt solution); hydrometers drift unreliably.

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Frequently asked questions

What does Salinity mean in fishkeeping?

Salinity is the concentration of dissolved salts in water, expressed as parts per thousand (ppt) or specific gravity (SG). Reef target: 35 ppt = 1.025-1.026 SG. Brackish: 5-15 ppt. Freshwater: 0 ppt. Measure with a refractometer (calibrated monthly with 35 ppt solution); hydrometers drift unreliably.