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We can help you navigate your way through all the types of lights in fish tanks and determine which type is best for your aquarium.
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
Discover how to hardscape your aquarium here at Petco. Visit Petco and check out aquarium hardscape ideas, solutions and much more for your fish.
Updated on November 13th, 2025
Learn how to care for a Tetra, recommended diet & habitat setup. Find the right food, supplies & equipment at your neighborhood Petco.
Updated on November 13th, 2025
Our top ten most important tips for removing and keeping algae out of your aquarium.
Updated on November 13th, 2025
The most common cause of death of a newly acquired fish is usually shock or incorrect water quality. Fish tanks should be set up and left running without fish for at least 3-4 weeks to establish a proper nitrogen cycle. There are products that can shorten this time period. If this is not done, there may be high levels of ammonia, chloramine, nitrates and nitrites which can kill a fish. When introducing a fish, the bag should be floated in the tank for about 30 minutes to acclimate the fish to water temperature. This can prevent shock if the water is too hot or too cold. Test your water quality with a home test kit or submit a sample for testing. Most pet stores or aquarists will do this for free or for a nominal fee. Correct any imbalances as indicated. Slowly acclimate any new fish as written above. You can request a consultation to discuss your concerns in greater detail if necessary. Buying fish and starting a tank can be quite confusing initially.
Updated on August 12th, 2025
At the very least, a 10 gallon tank with a filter, heater, hood and light. Ideally, the tank should be up and running (without fish) until it cycles properly. This means there needs to be sufficient time for beneficial bacteria to colonize the tank and filter to be able to break down wastes, namely ammonia and nitrites and to a lesser degree, nitrates. This can take several weeks to occur. You can cycle a tank with fish in it, but it will require daily testing of water chemistry to prevent a toxic build up of ammonia and/or nitrites. Either can kill your fish if not treated. Follow this link for a FAQ regarding Glo Fish: https://www.glofish.com/about/faq/ Follow this link for more about cycling a tank: http://www.firsttankguide.net/cycle.php
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
All these fish can grow quite large. The loach would be the "smallest" at about 6 to 8 inches when full grown. The Oscars can reach lengths of 18 inches and the Texas cichlid and sharks can reach a foot in length. All these fish will require much larger tanks than the ones you have now. The three Oscars alone would do best in a 125 gallon aquarium MINIMUM. The others may thrive in 55 to 75 gallon tanks. To leave them in small tanks will cause stress, aggression and likely infection.
Updated on August 12th, 2025
Goldfish are surface breathers so seeing them up at the top is not unusual. They are also very dirty fish, so I recommend getting a small pump for aeration and doing a partial water change. There is usually a period of cloudy water after establishing a new fish tank until the bacterial balance is established and stabilized in the tank. I also recommend getting a siphon--type tank cleaner so you can use it to clean the gravel as you remove some of the water. It acts as a vacuum to pull out all the fish poo that settles to the bottom, and the water you remove from the tank is a great thing to water any plants you have with, as it also fertilizes them. Remove no more than half of the tank's water and replace it with clean fresh water that has had the correct amount of water conditioner for the volume you're adding.
Updated on August 12th, 2025