How much

How much salt for a Waterbox Rimless 50.3?

Pre-calculated for the Waterbox Rimless 50.3 (30 × 20 × 18 in · raw volume ≈ 47 US gal · water volume ≈ 41 US gal).

By scenario

ScenarioAmount
Initial fill (cycling the tank)

13.4 lb (6083 g)

Or about 0.74 × 7 kg buckets / 0.23 × 22 kg buckets.

10% weekly water change

1.36 lb (615 g)

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

20% bi-weekly water change

2.72 lb (1230 g)

8.2 gal new saltwater every 2 weeks.

Annual salt budget (10% weekly)

71 lb (32.0 kg)

Plan on 5 × 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