Active ingredient: Amine-complexed (chelated) ionic copper
How to use (from the label): Target: 0.25 mg/L in FRESHWATER, 0.5 mg/L in saltwater, held 14 days. Dose: 1 mL per 40 L on day 1, repeat after 48 h (saltwater); half dose in freshwater. Limits: Do not exceed 0.6 mg/L; do not redose without a copper test. Prep: Remove invertebrates; turn off UV/ozone; remove carbon/Purigen; no other medications; no reducing-agent conditioners. After: Remove with carbon or CupriSorb, kept in at least a week after copper reads 0
Careful: Invertebrates are extremely sensitive and must be removed; not reef-safe. No carbon or chemical media during treatment (carbon removes it afterwards). Do not combine with any other medication, and above all not with formalin, aldehydes (ParaGuard) or reducing agents/dechlorinators such as Prime: these reduce Cu2+ to Cu+, which is about 10x more toxic. Toxic dose about 0.8 mg/L.
Never mix medicines unless the label says it is safe, and remove shrimp and snails unless the label says they are safe.
Examples you may see in shops: Seachem Cupramine. Not endorsements. Always follow the label.
4 facts checked with sources