Ich medication

Performance & sizing

Core numbers for matching this unit to your tank and electrical plan.

Power

—

Flow rate

—

Noise

—

Dimensions

—

Price range

—

Tank fit (L)

—

Consumables & maintenance

Follow the manufacturer schedule for seals, impellers, media, and other consumables.

Description

The spots are not the target, and that is the single most useful thing to know before dosing. Ichthyophthirius multifiliis, the freshwater white spot ciliate, feeds buried in the fish's epithelium and then drops off to encyst in the tank. The Merck Veterinary Manual is explicit that while encysted the parasite is refractory to chemical treatment. Each cyst releases hundreds of tomites that must find a host inside a window set by water temperature, and that free-swimming window is the only stage a medication can reach. Dosing is therefore repeated rather than heavy. Temperature sets the schedule. Above about 26 °C Merck has infected fish treated daily, with three to seven treatments commonly needed; colder water stretches the free stage from days into weeks and stretches the course with it. Stopping when the visible spots clear is stopping halfway, because the spots leaving the fish is the parasite entering the stage nothing can touch. Formalin and copper are the usual actives, and formalin is one of the few things the FDA has actually approved for the job: PARASITE-S is cleared for control of external parasites on cultured food fishes, with Ichthyophthirius named among the organisms controlled. Merck also lists raising salinity to 5 g/L for a week at 24 °C or above where the species tolerates it. Many hobby products pair formalin with malachite green; Merck calls that combination effective but flags the regulatory concerns around malachite green and tells veterinarians not to dispense it. Two measures come free with the tank. Ich cannot survive without living fish, so a fallow system starves it out, and because the cysts sit in debris, vacuuming gravel removes part of the next generation. It also travels between tanks on wet nets.

Sources

• merckvetmanual.com — https://www.merckvetmanual.com/exotic-and-laboratory-animals/aquarium-fish/parasitic-diseases-of-fish
• fda.gov — https://www.fda.gov/animal-veterinary/aquaculture/approved-aquaculture-drugs

Figures on this page were read off these pages. Manufacturers and databases do change or retire pages; if a link is dead, tell us with the correction link below.