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Search Petco to find out the harm of high nitrates in freshwater fish aquariums. We provide vital information to help keep your fish happy & healthy.
Updated on November 13th, 2025
Cotton wool disease is a common ailment that affects aquarium fish. Learn more about the signs, symptoms and treatment solutions at Petco.
Updated on November 13th, 2025
Learn how to care for freshwater community fish, recommended diet & aquarium setup. Find the right food, supplies & equipment at your neighborhood Petco.
Updated on November 13th, 2025
Learn more about these slow moving fish and the care they need when added to your aquatic environment.
Updated on November 13th, 2025
If you’re thinking of adding a betta fish to your family, learn a few fun facts about these underwater wonders.
Updated on November 13th, 2025
Goldfish need powerful filtration. Your filter should be rated for at least twice the tank volume. Once you get a test kit, check the chemistry. Aim for 0 ppm ammonia and nitrites with nitrates at about 40ppm. Use a kit that has liquid reagents, not strips. The liquid kit is more accurate. The pH should range between 7.2-7.6. Being cold water fish, goldfish thrive between 65F and 72F. You can dissolve 1 teaspoon of plain aquarium salt (NOT table salt) per gallon of water to use as a general tonic. It will reduce stress, improve gill function, treat minor infection and aid in recovery. Treat for 10-14 days then reassess the condition of your fish. When performing partial water changes, treat only the volume of water being replaced not the entire tank volume. Change no more than 30% of the volume at a time. Use only aged or conditioned water that is temperature matched to prevent stress or shock.
Updated on August 12th, 2025
Hi, and thanks for your question. This is a quite concerning presentation and it is likely to be related to water quality. Begin by submitting a water sample for quality testing. Most pet stores will do this for free or a nominal fee. Clinical examination should always include a water quality check, even if you have done so already. Water testing should be performed with a quality test kit, measuring NH4, NO2 and NO3. High ammonia levels, PH imbalances may be responsible for these signs. 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. Hope this answer was helpful, but 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. If this answer was helpful please let us know, this will be used
Updated on August 12th, 2025
Unfortunately this is a very generic sign and a radical approach must be followed in these cases to find the problem. 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 Fishy should 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 August 12th, 2025
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. Lack of oxygenation could be the cause of it. If water quality is good and there are no major imbalances, Bubbles should 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 (where you can post pictures ) if you have any more questions or to discuss it any further.
Updated on August 12th, 2025
Thanks for reaching out about your fish. Most of the water additives don't get absorbed systemically since fresh water fish do not drink water. A veterinary visit with a fecal sample is recommended to identify possible parasites and then prescribe a treatment. Most likely the medications needs to be top-coated on food and then eaten. Dosage depends on number of fish and estimated biomass (cumulative weight of fish). Good luck.
Updated on August 12th, 2025