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Learn how to safely handle your aquatic life to avoid toxin & bacterial exposure. Find aquatic life care supplies at your neighborhood Petco pet care center.
Updated on October 23rd, 2025
Learn how to pick the right aquarium plants, substrate, lighting, and fertilizers to ensure that your aquarium plants thrive and stay healthy.
Updated on October 23rd, 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 October 23rd, 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 October 23rd, 2025
Discover the fish tank filter system that’s right for your aquarium. Learn about mechanical, chemical, and biological filtration at Petco.
Updated on October 23rd, 2025
The width will limit the tank size. The largest tank would be a 25 gallon tank. If you choose this size, make sure the stand can support upwards of 300lbs. That is what the tank will weigh once filled and set up.
Updated on September 24th, 2025
It's not really recommended to keep fish in bowls with no filtration. And 2.5 gallons isn't really big enough for much. A Beta fish may possibly do ok in it if you can maintain it. But I would recommend more doing plants and a few snails or ghost shrimp type of animals in a bowl that size.
Updated on September 24th, 2025
The bowl looks definitively a bit small for the two fishes. To understand exactly what is going on you need to approach this problem radically but logically. 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.
Updated on September 24th, 2025
These signs are quite concerning and should be approached radically. 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.
Updated on September 24th, 2025
Check the water quality again use a liquid home test kit or submit a water sample for testing. The local Petco may do this for free or for a small fee Aim for an absence (0 ppm) of ammonia AND nitrites. Nitrates can be 20 ppm or less. Perform another partial water change, no more than 30% total volume, at a time. Use only conditioned water that is temperature matched to prevent stress or shock. Goldfish are cold water fish and do best between 65 F and 72 F. Additionally, a 10 gallon tank may be insufficient for 2 goldfish and a Black Moor. Goldfish produce a larger than average bio-load (waste) which can quickly overwhelm a small tank and after. Ideally, provide 20 gallons for one goldfish and an extra 10 gallons per fish. The filter should be rated for at least twice the volume of the tank. Even with a string filter, partial water changes and regular cleaning/vacuuming will be needed to maintain water quality.
Updated on September 24th, 2025