How much

How much salt for a Red Sea Reefer 170?

Pre-calculated for the Red Sea Reefer 170 (32 × 20 × 18 in · raw volume ≈ 50 US gal · water volume ≈ 43 US gal).

By scenario

ScenarioAmount
Initial fill (cycling the tank)

14.3 lb (6503 g)

Or about 0.79 × 7 kg buckets / 0.25 × 22 kg buckets.

10% weekly water change

1.42 lb (645 g)

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

20% bi-weekly water change

2.84 lb (1290 g)

8.6 gal new saltwater every 2 weeks.

Annual salt budget (10% weekly)

74 lb (33.5 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.

Affiliate links. As an Amazon Associate, reefcalcs earns from qualifying purchases.

Last reviewed