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Mineral Chemistry

Iodine (Reef Trace)

A trace element used by reef invertebrates - particularly important for shrimp molting, macroalgae, and some soft corals.

Unit: ppm Code: IODINE

📊 Ideal Ranges

Reef
0.04-0.08 ppm

📖 Overview

Iodine is one of the most-consumed reef trace elements. Shrimp use it during molting; some soft corals require it for pigmentation; macroalgae in refugia need it. Natural seawater contains 0.06 ppm. Reef supplements (Lugols solution, potassium iodide) replenish depleted iodine, but overdoing it toxifies corals. Test kits are reliable enough for occasional supplementation.