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Read about Habitattitude and Petco's commitment to protect our environment. At Petco, animals always come first. Learn how you can help.
Updated on November 13th, 2025
Visit Petco to learn about cleanup crews and how they can help your aquarium health.
Updated on November 13th, 2025
Wondering why you may need CO2 in your fish aquarium? Learn the basics from a Petco aquatics specialist.
Updated on November 13th, 2025

Small, AKA “Nano” tanks have grown in popularity over the past couple years and continue to gain momentum. Find out if a mini aquarium is right for you.
Updated on November 13th, 2025
Shop Petco for low-maintenance aquarium decorations like the El Nino fern. We want to help decorate your aquarium to keep your fish happy and comfortable.
Updated on November 13th, 2025
I would recommend to have the water completely changed. New water should be ideally submitted 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 as well. Oxygen concentration and quality of the filters should be determined as well. 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
Anytime there is an unexpected loss of fish, water chemistry should be checked. Use a home test kit ( https://www.petco.com/shop/en/petcostore/product/api-freshwater-master-test-kit# ) or submit a water sample for testing. Most pet stores will do this for free or for a small fee. Confirm an absence ( 0 ppm ) of ammonia and nitrites with a nitrate level of 20 ppm. pH can range between 6.5 and 8, water temp should be 65 F to 75 F. If chemistry and water quality are within normal parameters, then illness or aggression would be other reasons for the loss. It is always recommended to quarantine fish in a separate tank for 2-4 weeks prior to adding them to the main tank. During this time, they can be treating for infection or parasites. I am sorry for the loss of your fish.
Updated on August 12th, 2025
The best and safest method is through daily partial water changes, about 30-40% of total tank volume. Use only aged or conditioned water that is temperature matched to prevent stress or shock. Recommended water conditioners are AmQuel, NovAqua and StressCoat. These can be purchased online or in most pet stores or fish stores. A home test kit should be used to monitor levels. If a tank is properly cycled, beneficial bacteria will break down these toxins. Overfeeding, excessive light or heat and dead plants can cause spikes in ammonia and nitrite levels.
Updated on August 12th, 2025
Customers under the age of 18 cannot purchase live Companion Animals or Aquatic Life without a parent or guardian present. (Excluding crickets and worms). Due to the demands of time and intricate care required with certain species, it is in the best interest of the animals to not sell to minors. Parental permission at time of sale will ensure a better home for the animal and lower our rate of return.
Updated on August 12th, 2025
It is no trouble at all. It is why we are here! The first thing to check would be water chemistry. This can be done using a home test kit or by submitting a water sample for testing. Most pet stores will do this for free or for a small fee. Aim for 0 ppm ammonia and nitrites with a nitrate level of 20 ppm or less. Perform a partial water change, no more than 30% total volume, daily to stabilize or improve water chemistry. Use only aged or conditioned water that is temperature matched to prevent stress or shock. The species of fish you have do best in the mid to high 70s F up to about 82 F. If you have a newly set up tank, it may not have cycled properly or adequately. This would have led to toxic levels of ammonia which likely killed your fish. A tank needs to run, without fish ideally, for 4-6 weeks to establish a Nitrogen Cycle. This time period allows beneficial populations of bacteria to colonize the substrate and filter media. These bacteria are responsible for breaking down ammo
Updated on August 12th, 2025