How much

How much salt for a Red Sea Reefer 250?

Pre-calculated for the Red Sea Reefer 250 (36 × 22 × 21 in · raw volume ≈ 72 US gal · water volume ≈ 64 US gal).

By scenario

ScenarioAmount
Initial fill (cycling the tank)

21.0 lb (9546 g)

Or about 1.16 × 7 kg buckets / 0.36 × 22 kg buckets.

10% weekly water change

2.12 lb (960 g)

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

20% bi-weekly water change

4.24 lb (1920 g)

12.8 gal new saltwater every 2 weeks.

Annual salt budget (10% weekly)

110 lb (49.9 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