Quarantine Copper Treatment Protocol: Cupramine Dosing and Duration
Copper remains the most reliable weapon against marine ich, velvet, and Brook. Done right, it eradicates; done sloppily, it kills your fish instead of the parasites. This quarantine copper treatment protocol guide from Gensou Aquascaping at 5 Everton Park lays out precise Cupramine dosing, duration, testing cadence, and the species exceptions every Singapore marine keeper should memorise before dropping a single drop into a quarantine tank.
Quick Facts
- Cupramine therapeutic range: 0.35-0.5 ppm ionic copper, measured as total copper
- Duration: 14 days minimum at full therapeutic, 21-30 days for suspected velvet
- Testing frequency: daily for first week, every 2-3 days thereafter
- Ramp-up: day 1 half dose, day 2 full dose — never slam to target in one shot
- pH must stay 8.1-8.3; copper toxicity rises sharply below 8.0
- Invertebrates, corals, and elasmobranchs (rays, sharks) cannot tolerate any copper
- Remove all carbon, resins, and rock before dosing — copper binds and drops out
Why Copper Works
Ionic copper disrupts respiratory enzymes in protozoan parasites including Cryptocaryon irritans (marine ich) and Amyloodinium ocellatum (velvet). Fish tolerate copper at therapeutic levels because their larger cell structures metabolise it more slowly. The therapeutic window is narrow — below 0.35 ppm parasites survive; above 0.6 ppm fish kidneys and gills take serious damage.
Cupramine Over Other Coppers
Cupramine (Seachem) uses amine-complexed copper that stays bioavailable at stable concentrations. Ionic coppers like Copper Power work but drift more and are harder to test accurately. Chelated coppers bind more tightly and require higher doses (up to 2 ppm) that most test kits cannot measure. For Singapore hobbyists, Cupramine at $25-$35 per 250 ml bottle from Reef Depot, Iwarna, or Aquamarin is the standard. One bottle treats multiple quarantine cycles.
Tank Setup
Use bare-bottom glass, 40-80 litres for most fish. Include PVC pipe shelters, a heater set to 26-27 C, a sponge filter cycled on an established tank for at least three weeks, and an airstone. Absolutely no live rock, no sand, no ceramic media containing calcium carbonate — all bind copper and drop levels unpredictably. Plastic plants are fine. Turnover 5-10x hourly.
Pre-Dosing Checks
Confirm the tank is cycled — ammonia zero, nitrite zero. Confirm pH 8.1-8.3. Confirm the fish are eating. Remove all carbon, Purigen, Seachem Matrix, and similar media. Have a copper test kit ready. Seachem MultiTest Copper reads both free and total copper, which matters because Cupramine measures as total. API copper reads only free copper and will give you dangerously low readings on Cupramine — it is the wrong test for this drug.
Day-by-Day Dosing
Day 1: dose half therapeutic. Cupramine dosing is 1 ml per 40 litres to reach 0.25 ppm. Day 2: dose the second half to reach 0.5 ppm. Day 3: test. Top up any shortfall slowly. Repeat testing daily through day 7. Fish stressed by rapid copper rise will refuse food for 24-48 hours — this is normal, but if refusal continues past day 4, test kH and ammonia before assuming copper toxicity.
Duration for Common Pathogens
Marine ich (Cryptocaryon): 14 days at therapeutic is adequate because the parasite completes its lifecycle in 7-10 days at 26 C. Adding 4-7 days of buffer catches any laggards. Velvet (Amyloodinium): extend to 21-30 days due to faster, more aggressive lifecycle and higher lethality. Brook (Brooklynella): copper is less effective — use formalin or Ruby Reef Rally as primary, copper secondary. Uronema: copper does not work reliably — seek alternative protocols.
Ramping Down
After the full course, water change copper out gradually over 5-7 days. A 50% change on day one drops copper to 0.25 ppm; a second 50% two days later to 0.12 ppm; a third to near zero. Add fresh carbon after the third change to strip residual copper. Test twice to confirm zero before moving fish to the display.
Species That Cannot Tolerate Copper
All invertebrates — shrimp, crabs, snails, corals — die at any therapeutic copper dose. Rays and sharks lack the cellular mechanisms to metabolise copper and are severely poisoned. Mandarin gobies and other scaleless benthic species are extremely sensitive; use tank transfer method instead. Puffers handle copper poorly and often refuse food for the duration. Blennies and some tangs (particularly powder blue) can take it but may show mucous sloughing — monitor closely.
Combining with Other Meds
Copper runs fine concurrent with Prazipro (standard dose 2.5 ml per 40 litres, repeat after 7 days) for internal and external flukes. Do not combine copper with formalin — the combined gill stress can kill. Do not combine with Furan-2 or antibiotic courses without 48 hours gap, as metabolic load on fish compounds.
Common Mistakes
Relying on dosing maths alone without testing — copper drops as it binds to organics and any residual carbonate. Using API copper test on Cupramine and reading falsely low. Adding back live rock during treatment. Stopping at 10 days because “fish look clean” — parasites in encysted stage come back the next week. Moving fish to display while copper residual remains — kills the cleanup crew.
Post-Treatment Observation
After copper removal, hold fish in the quarantine tank for another 14 days observation. This catches any pathogens copper missed — bacterial infections, internal parasites, or resistant strains. Feed heavily with medicated food (Seachem Focus + MetroPlex + garlic) as the final prophylactic. Only then move to the display. Four to six weeks total quarantine is the standard among Singapore marine keepers with mature reef systems worth protecting.
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emilynakatani
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