Tank Transfer Method Marine Quarantine: Ich Eradication Without Copper

Copper knocks out Cryptocaryon irritans reliably, but it also rules out invertebrates afterwards and stresses sensitive species such as tangs and angelfish. The tank transfer method marine quarantine sidesteps medication entirely by moving fish between clean tanks on a timed cycle, starving the parasite before it can reinfect. This guide from Gensou Aquascaping in Singapore walks through the 3-days-by-4-transfers schedule, the gear needed, and the common mistakes that break the protocol. It suits hobbyists who want medication-free ich eradication without compromising rigour.

Quick Facts

• Protocol: 4 transfers, 72 hours apart (3 days each), total 12 days in quarantine
• Targets Cryptocaryon irritans (marine ich) by breaking the tomont-to-theront lifecycle
• No copper or chelated medications required; safe for invertebrate-bound livestock
• Requires two tanks rotated, each fully sterilised between uses
• Effective only against ich; add prazi or formalin dips for flukes separately
• Temperature held at 26-27°C throughout to maintain predictable parasite cycle
• Fish still need 2-4 weeks observation after the 12-day TTM before reef introduction

Why Tank Transfer Works

Marine ich has a multi-stage lifecycle. The trophont feeds on fish for 3-7 days, drops off as a tomont, then releases free-swimming theronts within 3-28 days. By moving the fish to a completely clean tank every 72 hours, any tomonts released in the old tank are left behind with no host to infect. Four cycles cover the fastest-releasing tomonts and any stragglers that detach on transfer day.

Copper-free treatment matters for fish that react poorly to chelated copper, such as Centropyge dwarf angels, some wrasses, and anthias. It is also the only quarantine option if the destination tank holds cleaner shrimp, snails, or corals.

Equipment You Need

Two identical bare-bottom quarantine tanks of 40-80 litres each, two sponge filters run ahead of time in a healthy tank for biological capacity, two heaters set to 26°C, two lids, and a dedicated net per tank. Add PVC elbows or ceramic caves for hiding. Avoid sand, rocks, or anything porous that cannot be bleached between uses.

Budget in Singapore runs roughly $150-250 for a pair of basic tanks, sponge filters, and heaters from Serangoon North shops. Have ammonia and pH test kits on hand, plus seachem prime for emergency neutralisation.

The 72-Hour Transfer Schedule

Day 0: acclimate fish into Tank A. Day 3 (hour 72): net fish into pre-mixed saltwater in Tank B, matched to the same temperature and salinity (1.025 SG). Day 6: transfer to freshly scrubbed Tank A. Day 9: back to Tank B. Day 12: final transfer complete, fish moves to observation quarantine or display. Missing the window by more than 4-6 hours compromises the cycle because early theronts may appear.

Between transfers, bleach the vacated tank with a 1:10 household bleach solution, rinse thoroughly, air-dry for several hours, then refill with new saltwater. Sponge filters cannot be bleached; rotate two pairs, cycling one pair in a seeded tank while the other is in use.

Water Parameters to Hold

Salinity 1.024-1.025, temperature 26-27°C, pH 8.1-8.3, ammonia 0, nitrite 0. Feed lightly during transfers to keep bioload manageable. If ammonia creeps up because the sponge filter lost its colony, dose prime every 24 hours and bring a fresh sponge from the display sump. Cooler Singapore evenings rarely drop a heated quarantine below target, but check that aircon airflow does not chill the tank unevenly.

What Tank Transfer Does Not Treat

TTM works against marine ich only. It does not eliminate Amyloodinium (velvet), flukes, brooklynella, or internal parasites. Pair TTM with a freshwater dip and a prazipro treatment in the final observation tank if flukes are suspected. For velvet, copper or chloroquine phosphate remains the reliable treatment since the parasite’s reproductive cycle can outpace the transfer schedule.

Common Mistakes That Break the Protocol

Skipping a transfer because the fish looks healthy is the most frequent failure. Tomonts can sit dormant for days before releasing theronts, and a single missed cycle can restart the infection. Reusing a net between tanks, leaving residual water on a thermometer, or forgetting to sterilise the heater all reintroduce the parasite. Use colour-coded equipment per tank.

Salinity swings between pre-mixed batches also stress fish mid-transfer. Mix both new batches from the same salt tub and let them circulate for 24 hours with a heater and powerhead before use.

Post-TTM Observation

After the final transfer, move fish to a long-term quarantine tank for at least two weeks of observation. Watch for delayed flashing, rapid breathing, or white spots returning. If the fish clears observation cleanly and has been eating well, it is ready for the display tank. This two-stage approach keeps the display reef free of parasites indefinitely when combined with a strict new-arrival policy.

Related Reading

How to Set Up Marine Quarantine Tank
How to Quarantine Marine Fish Complete
Marine Ich Cryptocaryon Treatment
How to Acclimate Marine Fish Drip Method
Best Aquarium Quarantine Kit