How long to wait before adding new fish after ich treatment?
Updated On September 23rd, 2025
I recently lost more than half of my fish tank due to ich. I did the “super ick” medicine and managed to save the remaining fish in my tank. I was wondering when it was safe to introduce new fish into my tank so that I can rebuild it.
2 Answers
Most Helpful Answer
Published on February 1st, 2020
If the infection is cleared, wait a couple weeks and then consider repopulating the tank. Ideally, you should set up a quarantine tank for incoming fish before they go into the main tank. Monitor them for a week or two to confirm good health. You may even want to administer an antiparasitic medication while in quarantine to be safe.
1Pet Parents found this answer helpful
Related Answers from Veterinarians
-
Published on September 3rd, 2017
The best way to make sure the new fishes are not infected is to place all new fishes in a quarantine tank for at least 2-3 weeks to make sure they are eating, free of disease, and are able to recuperate in a stress-free environment. No preventive treatment needed. Please do not hesitate to contact us again on the forum or by requesting a consultation if you have any more questions or to discuss it any further.
1Pet Parents found this answer helpful
Health & Wellbeing
All I read above is good info. So I placed the ick infected fish in a QT tank, turned up the heat to 79 and added air stone in it. Prior to That I had treated them for 6 days with ich meds. It the last couple days they have been clear. How long onc
Ideally, the tank should be kept at about 86 F for two weeks to resolve Ich infection. The gravel or substrate should be vacuumed and tank furniture sanitized. If you are setting up the tank anew, you will have to allow time for it to properly cycle prior to adding fish.
Updated on September 24th, 2025
Health & Wellbeing
Hi, Got a marine fish tank 120L. The blue tang got white ich a week back and it died and post that within a week all the other fishes died. Had a pair of clowns and various damsels. Now with no fishes in the tank, what should I do next? I plan to
Ich (Cryptocaryon) is an obligate parasite. This means it needs fish to survive. If your tank has no fish, continue to run the filter and tank empty for at least 6 weeks. You can increase temp to about 86 F to speed up the life cycle of the parasite. If your tank is not a reef tank and has no inverts, you can treat the tank with copper. Once treatment is complete, decrease temps to normal ranges. Continue to monitor salinity/chemistry. Quarantine any new fish for at least 10 days in a bare bottomed, established tank to prevent re-introduction of parasites into the main tank.
Updated on September 24th, 2025
Health & Wellbeing
can you use a treatment for ich as a preventative medicine in new water before you add fish to it? if so which medicine?
The best way to make sure the new fishes are not infected is to place all new fishes in a quarantine tank for at least 2-3 weeks to make sure they are eating, free of disease, and are able to recuperate in a stress-free environment. No preventive treatment needed. Please do not hesitate to contact us again on the forum or by requesting a consultation if you have any more questions or to discuss it any further.
Updated on September 24th, 2025
Health & Wellbeing
My 10 gal freshwater tank has been infected with ich. I am treating the tank, but still my fish are dying. If I were to just clean it out and start over with fresh water, new substrate, and a clean tank, would that get rid of the ich? Can I clean it
First, perform a partial water change, vacuum gravel thoroughly and wipe down any tank furniture. This is critical because clean water is the cornerstone for treatment and recovery. Use only conditioned water that is temperature matched to prevent stress or shock. Next, you can use any one of the commercial ich medications, such as Ich Guard (Tetra), Super Ick Cure (API) or Rid Ich Plus (Kordon). These can be found in the Aquarium section of the local Petco. Follow label directions carefully. This method will typically work with most fish. Another option would be to use plain aquarium salt ( NOT table or Epsom salt). Dissolve 1 tablespoon of salt per 5 gallons of water in a cup or two of tank water and gently pour it into the tank. At the same time, gradually increase the water temp to about 86 F. Hold it there for 14 days. The warm temps will speed up the life cycle of the parasite and the salt will kill it. Afterwards, gradually reduce water temp and perform another partial water ch
Updated on September 24th, 2025
Health & Wellbeing
If the fish are moved from the main tank into a quarantine tank and the ich falls off in the quarantine tank how does the exsisting ich fall off and not reattach itself to the fish that are quarantined?
When there is an ich infection, it is necessary to treat the entire tank, even the fish that are not symptomatic. Ich has 3 distinct stages in the life cycle. Tomites, the free swimming stage, are most vulnerable to treatment. Once on the fish or encapsulated in the substrate, ich is very difficult to treat. A combination of increased water temp, aquarium salt and commercial medication can be used to treat ich. The increased water temp, 86F, will significantly speed up the lifecycle. It can take 1-2 weeks to treat minor infections and longer for more severe infections.
Updated on September 24th, 2025
Health & Wellbeing
Most people don’t have the money and space to run a quarantine tank. When introducing new fish (without visible ich spots) could I assume that there are ich tomites. Could I do an ich treatment and prevent a full outbreak. ( I have just been throug
If a QT tank is not available, then prophylactic treatment can be done on new fish. Methylene blue or malachite green, providing your chosen fish are not sensitive to either, can be used on Day 1 and then again on Day 4. A commercial ich treatment can be used instead as well. Be sure to treat any plants as well.
Updated on September 24th, 2025
Health & Wellbeing
Hello, I was wondering how one would introduce new fish to a aquarium that already has preexisting fish. Whenever I add new koi fish to my collection, most if not all of my old koi fish die from diseases. Can you explain how this process could be don
Ideally you would quarantine any new Fish in a separate aquarium for a few weeks to make sure they do not show any signs of diseases or infection. Once 2-3 weeks have passed without any signs of a problem then it is usually pretty safe to introduce to the common aquarium. Good luck and I hope they do well!
Updated on September 24th, 2025
Health & Wellbeing
Hi my fish has white spot and i am treating it.how long should it approximately take to cure?
Ich, or white spot disease, can take about two weeks to treat. You can increase water temp gradually to 86F. This will speed up the ich lifecycle. Once the spots fall off your fish, vacuum the substrate thoroughly, clean plants or tank furniture and rinse the filter media (with tank water). You can use a commercial ich treatment or dissolve 1 teaspoon of aquarium salt (NOT table salt) per gallon of water into the tank. Either are effective when used in conjunction with a temp increase. Whichever method you choose, treat for about 5 days after the last symptoms resolve then gradually decrease water temp back to normal for goldfish. This would be between 65F and 72F.
Updated on September 24th, 2025
Health & Wellbeing
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 treatm
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.
Updated on September 24th, 2025
Health & Wellbeing
Hi, I was wondering if my discus fish has ich. It has white spots, but has been moving around and eating like crazy. It is new to my tank,(1 week) and has beeb acting normal. I am conserned and what to catch the ich early if it does have ich. My tank
It is difficult to determine since the image is not clear. Fish are very hard to photograph! If it does, then it is very early infection. Ideally, new fish should be quarantined for at least 2 week sin a separate tank to confirm good health prior to introducing them into the main tank. Monitor for worsening symptoms. If necessary, you can purchase an ich treatment and treat the tank. Look in the Aquarium section of the local Petco. Follow label directions and remove the carbon filter insert during treatment if indicated.
Updated on September 24th, 2025
Have A Vet Question?
Book an appointment with the pros – our expert vets are here to help.
