Waterbox Reef Salt | Synthetic Marine Salt Mix for Mixed Reefs & SPS

Waterbox Reef Salt is a synthetic marine salt mix engineered specifically for mixed reefs and SPS-dominant systems. Loaded with major and minor trace elements at reef-stable levels, it dissolves ultra-fast and clean for confidence-inspiring water changes — and every batch is ICP-OES tested every 2,000 lbs to guarantee consistency. Available in 5 KG / 11 LB and 20 KG / 44 LB box sizes.

Browse more in our salt mixes collection or shop the full saltwater lineup.

Why Reefkeepers Choose Waterbox Reef Salt

• Designed for mixed reefs & SPS — formulated specifically for the demanding water-chemistry needs of stony coral systems.
• Synthetic reef salt mix — no harvested seawater, no inconsistencies; every box mixes to the same target.
• Full major & minor trace elements — calcium, alkalinity, magnesium plus the trace elements corals consume.
• Ultra-fast and clean mixing — dissolves quickly with no residue, so you can do same-day water changes.
• ICP-OES tested every 2,000 lbs — independently verified consistency from box to box.

Mixing & Usage

Standard salinity: Mix to a target specific gravity of 1.025 (35 ppt). Use RODI water and an accurate refractometer for best results.

Approximate ratio: Roughly ½ cup of salt per gallon of RODI water; always confirm with a refractometer.

Aerate & circulate: Mix in a clean container with a powerhead for at least 1–2 hours (or overnight) before use. Match temperature to your display before adding.

Water changes: Replace 10% weekly or 20% bi-weekly to maintain stable parameters in mixed reef and SPS systems.

Specifications

Recommended Pairings

• Saltwater Refractometer — verify salinity every batch.
• Hanna HI96822 Digital Refractometer — lab-grade accuracy for salinity.
• Red Sea Reef Foundation Pro Test Kit — track Ca, Alk, Mg between water changes.
• Hanna Marine Coral Care Kit — full-suite reef testing.
• Waterbox Calcium, Alkalinity & Conditioner — round out your Waterbox water-care system.
• Browse all salt mixes if you'd like to compare alternatives.

Frequently Asked Questions

Is this salt good for SPS?
Yes — Waterbox Reef Salt is formulated specifically for mixed reefs and SPS-dominant systems, with elevated alkalinity and trace element levels SPS corals demand.

How fast does it mix?
Waterbox Reef Salt is engineered for ultra-fast, clean mixing. With proper circulation and aeration, it typically dissolves clear within 30–60 minutes; we still recommend at least an hour (or overnight) before use to ensure full equilibration.

How many gallons does each box make?
Approximate yield depends on target salinity, but the 5 KG / 11 LB box mixes roughly 35–40 gallons and the 20 KG / 44 LB box mixes roughly 140–160 gallons at 1.025 SG. Always verify with a refractometer.

Why does ICP-OES testing matter?
Synthetic salt mixes can drift batch-to-batch if not monitored. ICP-OES testing every 2,000 lbs verifies that each production run hits the same trace-element targets — so the salt you buy today mixes to the same chemistry as the salt you bought last month.