How much

How much salt for a 65 gallon?

Pre-calculated for the 65 gallon (36 × 18 × 24 in · raw volume ≈ 67 US gal · water volume ≈ 59 US gal).

By scenario

ScenarioAmount
Initial fill (cycling the tank)

19.6 lb (8886 g)

Or about 1.08 × 7 kg buckets / 0.34 × 22 kg buckets.

10% weekly water change

1.95 lb (885 g)

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

20% bi-weekly water change

3.90 lb (1770 g)

11.8 gal new saltwater every 2 weeks.

Annual salt budget (10% weekly)

101 lb (46.0 kg)

Plan on 7 × 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