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Chemistry Chemistry

Copper (Toxicity)

A heavy metal toxic to fish and lethal to invertebrates - but a primary treatment for many marine parasites at controlled concentrations.

Unit: ppm Code: COPPER

📖 Overview

Copper is a paradox. At 0.15-0.25 ppm it kills marine parasites - the gold standard for ich and velvet in fish-only tanks. But it kills invertebrates, corals, and beneficial bacteria at those same concentrations. Copper treatments are done in bare quarantine tanks, never in the display tank. Once copper is in a tank, removing it is difficult - it binds to substrate, live rock, and equipment.

🧪 Testing Methods

Salifert Copper Test (during treatment). Seachem MultiTest Copper. Digital copper meter.

🩺 Related Diseases

Used to treat marine ich (Cryptocaryon), velvet (Amyloodinium), and other saltwater parasites.