My fish has white growth in its mouth and can't eat. Is it Columnaris?

That doesn't look like Ich infection. Ich typically presents as multiple salt grain sized dots on a fish. The area in the image may be an abrasion. Infection, fungal or bacterial, is possible. The Sera Omnipur may help if there is fungal infection. Be aware the malachite green in it may stain tank furniture or tank sealant. Consider adding in a broad spectrum antibiotic. You should be able to find one in the aquarium section of the local pet or fish store. Follow label directions carefully and remove the carbon filter insert during treatment if indicated. Maintain pristine water quality during treatment as well as afterwards.

The white fuzz may be Columnaris, an infection causing bacteria, or a fungal infection. It can be difficult to differentiate without microscopic examination. Either can be managed/treated via partial water changes, plain aquarium salt (NOT table salt) and medications. Partial water changes, no more than 20-30% daily, will stabilize chemistry and maintain or improve water quality. Use only aged or conditioned water that is temperature matched to prevent additional stress or shock. Aquarium salt can be used at 1 tablespoon per 5 gallons of water. Dissolve in a few cups of tank water and gradually pouyr it into the tank. Treat for 10-14 days then reasses the condition. When performing water changes, treat only the volume of water being replaced, not the entire tank volume. A methylene blue dip can be done daily. You can find it in the aquarium section of the local pet or fish store. A concentration of 50ppm is recommended. Do not add it to the main tank as it will turn everything blue and kill beneficial bacteria in the filter and substrate. Use a separate container and dip the fish for a few seconds, rinse and return it to the main tank. In the future, quarantine any new fish for several days to prevent introduction of disease to existing populations.

If it is fuzzy, it is likely fungal. You can try with a commercial antifungal medication such as API Fungal Cure, methylene blue or Pimafix/Melafix. These can be purchased online or in the aquarium section of most pet stores. Read package directions carefully and remove the carbon insert from the filter before treatment if indicated. Plain aquarium salt (NOT table salt) can be used in conjunction with one of the above treatments to aid healing. Dissolve up to one tablespoon per gallon of water into the tank. Fungal infections can take up to two weeks to resolve with treatment. Maintain proper water parameters (0 ppm ammonia/nitrites, 40ppm or less nitrates and temp of 65 F to 72 F). If possible, remove the affected fish yo a hospital tank during treatment.

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.

Thanks for reaching out about Rhino. An infection is likely, but first check water quality parameters such as pH, ammonia, nitrites and nitrates. Correct any abnormalities. Infections around the mouth can be caused by multiple bacteria, but Edwardiella caused a disease called enteric red mouth. Laying on the bottom probably indicates the infection has spread to the swim bladder, causing it to fill with pus or fluid. Systemic antibiotics are needed. Antibiotics added to the water will probably do nothing. A veterinary visit is recommended to help with diagnosis and a treatment plan. Good luck.

This could be either a bacterial infection, such as Columnaris, or a fungal infection, such as Saprolegnia. It is difficult to say without an exam or image. Either can be treated with medications found in the aquarium section of the local Petco. Look for an antifungal or antibiotic. You may even find a combination product. Follow label directions carefully and remove the carbon filter insert during treatment. Maintain pristine water quality via filtration and regular partial water changes. If an antifungal does not work, try an antibiotic or vice versa. Keep water temp between 78 F and 80 F.

It may be a bacterial infection or trauma. Monitor for bullying since you have other fish. Most minor infections can be managed or resolved by maintaining pristine water quality. A bit of plain aquarium salt (NOT table or Epsom salt) can be used as a general tonic to aid in recovery, reduce stress and improve gill function. Dissolve 1 tablespoon per 5 gallons of water in a cup or two of tank water and gently pour it into the tank. Treat for 10-14 days then reassess the condition. If the condition is unchanged, 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.