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When do ich meds kill parasites after they fall off Oscar fish?

Updated On September 23rd, 2025

Pet's info: Fish | Unknown - Fish

hello i am about 5 to6 months into the hobby my oscar fish have brought ich into my 75 gallon tank i am treating it with meds and salt and turned my temp to 83 will the meds kill the ich when they fall from my fish into the water ? started the treatment on friday the meds say do for 7 days then a 25 percent wc is their anyway to be sure they are all dead and gone ? thanks

1 Answer

Most Helpful Answer

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Answered By Angel Alvarado, LVT

Licensed Veterinary Technician

Published on August 20th, 2018

Increase the temp, gradually, to 86 F and hold it there for at least two weeks. This will speed up the ich lifecycle. When the parasite is free swimming is when it is most susceptible to treatment. Once the spots drop off your fish, perform a major water change and vacuum the substrate thoroughly. If you have live plants, remove them and gently wipe them down, if you have artificial plants, remove them and sanitize them. The same goes for any tank furniture. Use the ich medication according to label directions. Keep the water temp elevated for 3-5 days after treatment and after all symptoms have resolved. Gradually reduce water temp back to normal afterwards. There is no definitive way to determine if the infection is resolved. You will to monitor the fish closely and repeat the process if necessary.

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