How much

How much salt for a Standard 75 gallon?

Pre-calculated for the Standard 75 gallon (48 × 18 × 21 in · raw volume ≈ 79 US gal · water volume ≈ 69 US gal).

By scenario

ScenarioAmount
Initial fill (cycling the tank)

22.9 lb (10377 g)

Or about 1.26 × 7 kg buckets / 0.40 × 22 kg buckets.

10% weekly water change

2.28 lb (1035 g)

6.9 gal new saltwater. Many reefers settle here as a routine.

20% bi-weekly water change

4.56 lb (2070 g)

13.8 gal new saltwater every 2 weeks.

Annual salt budget (10% weekly)

119 lb (53.8 kg)

Plan on 8 × 7 kg buckets per year.

Brands hobbyists actually use

Buckets reefers actually buy at this volume. Coral Pro for high-alk SPS, Pro Reef for low-alk dosing tanks, Reef Crystals for budget mixed reefs.

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Last reviewed