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Learn how to test your aquarium water. Poor water quality stresses fish, which leaves them susceptible to disease and possibly death.
Updated on November 13th, 2025
GloFish are brilliantly colored and beautiful fish. Learn how to care for GloFish, what to feed them, how long they live, their ideal tank size and more.
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
Habitattitiude™ commits to environmental protection by not releasing unwanted fish into public areas.
Updated on November 13th, 2025
Learn about nitrates in your saltwater aquarium. Find out what is safe for your fish and how to improve your aquarium’s nitrate levels.
Updated on November 13th, 2025
Before you buy any fish, you will need to set up the tank. A basic set up includes: a tank, filter, hood/light, heater, gravel and some decor. The tank should run without fish for at least 4 to 6 weeks. This gives it time to cycle. The Nitrogen Cycle is critical to the health of the tank and any fish you will be keeping. During this time, beneficial bacterial will populate the filter and substrate (gravel). These bacteria will be responsible for breaking down fish wastes and other wastes (uneaten food, dead plants, etc.). You will need a home test kit to monitor water chemistry (ammonia, nitrites, nitrates, pH) or you will have to submit water samples for testing. Most pet stores will do this for free or for a small fee. At first, you will see high levels of ammonia and nitrites. Over time, as bacteria grow, these levels will drop. When ammonia and nitrites are at 0 ppm and nitrates are below 20 ppm, you can consider adding fish. Regular (every 1 or 2 weeks) partial water changes as we
Updated on August 12th, 2025
There are different ways to control algae accumulation inside the tank: Limit the nitrate accumulation in it (regular water changes is the most common method of removing nitrate), limit the lighting period in the aquarium (4 hours a day) avoid overfeeding. Try Algone, very effective against nitrate, it is not an algaecide but it can control indirectly algae. If all these methods are not effective, algaecide are then needed.
Updated on August 12th, 2025
If you put an Oscar in with your Tetras, they will be harassed and eventually eaten. Use a home test kit or submit a water sample for testing to check chemistry. Aim for 0 ppm ammonia and nitrites with a nitrate level of 20ppm or less. It can be slightly higher if you have live plants. If there is still ammonia present, the tank is still cycling. The cloudiness may be micro-bubbles which will eventually resolve or it could be a bacterial bloom which will also resolve once the tank has cycled.
Updated on August 12th, 2025
Thanks for reaching out about Diesel. This surely points to water quality issues. Have you tested the ammonia, nitrites and nitrates? Any chance of copper in the system? Parasites and bacteria rarely cause death this quickly. Remove all fish and place in new tanks, with spring water (bottled or reverse osmosis). Change or add carbon filtration. Good luck.
Updated on August 12th, 2025
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, impro
Updated on August 12th, 2025