How much

How much salt for a Standard 55 gallon?

Pre-calculated for the Standard 55 gallon (48 × 13 × 21 in · raw volume ≈ 57 US gal · water volume ≈ 49 US gal).

By scenario

ScenarioAmount
Initial fill (cycling the tank)

16.1 lb (7325 g)

Or about 0.89 × 7 kg buckets / 0.28 × 22 kg buckets.

10% weekly water change

1.62 lb (735 g)

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

20% bi-weekly water change

3.24 lb (1470 g)

9.8 gal new saltwater every 2 weeks.

Annual salt budget (10% weekly)

84 lb (38.2 kg)

Plan on 6 × 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