The theory behind the tank transfer method for treating Cryptocaryon irritans is to move a fish from one tank to the other when the parasites fall off the fish. This happens during dark times in the aquarium so moving the animal first thing in the morning is preferred. The parasites that fall off do not have the ability to complete the life cycle and re-attach. This involves transferring the fish every 3 days to a clean tank for at total of 4 transfers. The parasites that leave the fish are left in the empty tank. Once exposed to ich,the tank and all materials and equipment need to be dried thoroughly before reuse to insure all the parasites die. I feel that the tank will dry fine overnight if toweled dry. It's pretty easy with small tanks and limited equipment and ammonia becomes less of an issue given only a 3 day stay. I recommend the usage of ammonia detoxifier , just in case. Since the originating tank is a QT tank, simply drain it, clean it, and reestablish it for the next tank transfer. The filter floss used as a seeded biological filter is tossed as is all water. Any PVC is sterilized and any transfer equipment as well. This depletes and eventually eliminates the parasites available to reattach and as a consequence will create a parasite free fish. This is not without stress to the fish but it is in some ways better than copper and just as effective as either copper or hyposalinity. I personally advocate a transfer not using nets.
In the ocean the density of parasites is very low whereas in the aquarium, even larger aquaria, the density is comparably high. Since fish tend to sleep in the same place, and since parasites drop at night, the odds of reinfection are exceptionally high. Tank transfer eliminates CI by reducing density and reduces reinfection rate.
