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Related Articles & Questions
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- Vet Q & A
Why are my koi losing scales and goldfish have white head bumps?
This could be bacterial or parasitic infection. It is difficult to determine definitively since the image provided is not clear. Fish can be difficult to photograph. Basic care includes checking water quality and chemistry. This can be done using a home test kit or by submitting a water sample for testing. The local Petco may do this for free or for a small fee. There should be an absence of ammonia and nitrites with nitrates at 20-60 ppm. pH should be as close to 7 as possible, avoiding large swings. Koi can tolerate a wide range in temperature, but generally do best between 65 F and 75 F. Again, avoid large swings in temperature to prevent stress or shock. If necessary, a partial water change can be done to stabilize chemistry and/or improve water quality. If you have other koi, consider placing this one in a hospital tank to make treatment easier and to prevent spread if the condition is infectious. Plain aquarium salt (NOT table or Epsom salt) can be used to reduce stress, improve gill function, treat minor infection and aid in recovery. 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 14 days then reassess the condition. If there is no change, consider a broad spectrum antibiotic or "all in one" treatment. Either can be found in the Aquarium section at Petco. Follow label directions carefully and remove the carbon filter insert during treatment if indicated. All that said, if the spots multiply and appear like tiny grains of salt, it could be an ich infection. In this case the entire tank will require treatment. There are several commercial ich medications that can be used. You will also need to thoroughly vacuum the substrate/gravel in the tank and wipe down all tank furniture.
Updated on September 24th, 2025
- Vet Q & A
My fish have growths, tattered fins, and are flashing. What's wrong?
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.
Updated on September 24th, 2025
- Vet Q & A
What's the real difference between reptile and fish tank water conditioner?
Reptile water conditioner usually contains chemicals such as Water, Dechloraminating Agents, Synthetic Organic Polymers (Colloids), Chelating Agents, Electrolytes. The reptile conditioner usually also has a chemical that binds calcium in the water as well as a slime protecting agent that is good for amphibians and fish. Aquarium water conditioners (for fresh water fish) contains chemicals such as sulfates such as sodium thiosulfate. Thiosulfate is a Redox reducing agent. Either should be ok for reptiles or fish, however I would stick with reptile conditioner for reptile tanks or mixed (reptile and fish) tanks and for aquaria with fish only I would use specific aquarium water conditioner. The main reason to use a water conditioner is to remove chlorine in water. This, however, can also be attained by leaving the aquarium water fresh from the tap sitting over night. The chlorine will dissipate.
Updated on September 24th, 2025
- Vet Q & A
Why do my fish keep dying in my newly set up aquarium?
It is possible the tank has not cycled properly which results in high ammonia and nitrite levels which can kill fish. Allow the tank to run, without fish, for at least 4-6 weeks. During this time, use a home test kit or submit a water sample for testing every few days. The local Petco may do this for free or for a small fee. What you are looking for is to have ammonia and nitrites at 0 ppm and nitrates at 20ppm or less. pH can hover around 7 for most community fish. Avoid large, rapid swings in pH though. What is happening in the tank during this time is that beneficial bacteria are populating the gravel/substrate and the filter. These bacterial populations are responsible for the Nitrogen Cycle. This cycle breaks down wastes from fish, uneaten food and plant matter into by-products that are filtered out or dissipate. You can "cycle" a tank with fish, however this increases the risk of loss. Once your tank has cycled, you can add fish. You will still need to monitor water chemistry and perform partial water changes regularly. Use only conditioned water that is temperature matched to prevent stress or shock. You will also need to vacuum the gravel regularly and rinse the filter media. Never use tap water to rinse. Use a bit of tank water to protect bacterial populations in the sponge.
Updated on September 24th, 2025
- Vet Q & A
My fish is laying on the fake plant and barely moving. What's wrong?
There are several causes that can provoke these signs fro water imbalances to specific diseases like swim bladder ones. This problem requires a quite radical but logic approach. Begin by submitting a water sample for quality testing. Most pet stores will do this for free or a nominal fee. High ammonia levels, PH imbalances may be responsible for that. Oxygen concentration and quality of the filters should be determined as well. If water quality is good and there are no major imbalances, your fish should get examined to look for any sign of bacterial/fungal infection and eventually water should be treated. 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
