My fish is rubbing and acting strange. Is it parasites? What's safe for my tank?

By your description, the condition could be resolving. A bacterial, fungal or parasitic infection could have been the cause. It could also have been a traumatic injury. Monitor for signs of ich or bacterial infection. Move Mushu to a small quarantine tank or bowl. Maintain the water temp at 78-80 F. If it is ich, this will speed up the lifecycle. Dissolve 1 teaspoon per gallon of aquarium salt (NOT table salt) into the hospital tank. Perform daily water changes with conditioned water and fresh salt. Do this for 7-10 days maximum. A wide variety of minor infections can be treated in this manner. You can treat the main tank in this fashion if necessary, but perform 25-50 % water changes to avoid upsetting the nitrogen cycle.

It doesn't look like Ich in the images provided. Ich will appear as multiple white dots the size of salt grains on the fish. The fish will "flash" or dart about the tank and rub on objects due to itching. The fish may have an infection or the loss of scales may be due to trauma from other fish. Consider separating the affected fish into a separate tank to recover. If this is not possible, maintain pristine water quality in the main tank and consider a broad spectrum antibiotic. You can find one in the aquarium section of the local Petco. Follow label directions carefully and remove the carbon filter insert during treatment if indicated. You are likely at the maximum number of fish in the tank. As they grow, they shouldn't get bigger than 2 - 2.5 inches, and reach adulthood you may need a larger tank or you may need to separate them.

It could be early ich (white spot) infection or another infection (bacterial or fungal). To be safe, separate him into a quarantine tank and monitor for any change. You can treat for ich as you did it in the past if indicated. Bacterial and fungal infections have different treatments, so I would be hesitant to recommend a specific medication without more information or a definitive diagnosis. You can use plain aquarium salt (NOT table salt or Epsom salt). As a general tonic to reduce stress, increase gill function, treat minor infection of many types and to aid in recovery. This can be added to the quarantine tank at 1 teaspoon per gallon of water. Treat for 10-14 days then reassess the condition.

It sounds like they have "ich". Here is a good video about ich that should answer most of your questions. ( https://www.youtube.com/watch?v=gVwyOifCRHI ) I suggest you talk to an aquarist in your area to get some medication. ( https://www.yelp.com/biz/aqua-life-aquarium-rocklin-2?osq=aquarium+store ) Hope this helps. Best wishes.

Thanks for reaching out about Dart and including photos. The lesions are not clearly visible in the pictures but by the description, could be parasitic as in salt water ich (cryptocaryon). A veterinary visit could provide diagnostic services, as a skin scrape and recommend a treatment plan. Other fish will be affected so treatment should include the entire aquarium. Good luck.

Non-iodized salt can be used as an immersion bath (short term) at 10-30 g/L for up to 30 minutes. Keep a close eye on the fish for stress or rapid respiration as some fish can only tolerate the higher dose for minutes. This can be repeated every 2-3 days. It is difficult to determine in the pictures whether this is a parasitic problem or not. Black areas can be the result of melanin pigments, a sign of trauma. A visit to a veterinarian acquainted with fish could perform a skin scrape and examine under the microscope for a diagnosis. Good luck.

Thanks for reaching out about your aquarium and including photos. Did you test your water quality prior to the water change? Continue to test for pH, ammonia, nitrites and nitrates. Pristine water quality is needed for health. Are any of the fish new, that could have introduced parasites? Itching/flashing can be due to water quality, external parasites, bacterial or viral infections and other causes. The white lesions on the photo could be fungal infections. A skin scrape and examination under the microscope (at a veterinarian's office) is needed for an attempt to determine a cause. Fungal infections are often secondary problems, so check water quality first. Good luck.