Two Easy Ways to Start Earning Rewards!
Earn 2X Pals Rewards points at Petco
when you use Petco Pay!
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
Find out which freshwater fish can live together with our compatibility chart and tips for creating a harmonious aquarium.
Updated on November 13th, 2025
Learn how to care for Fang Blenny, recommended diet and aquarium setup. Find the right food, supplies and equipment at your neighborhood Petco.
Updated on November 13th, 2025
Learn how to care for a starfish, recommended diet and aquarium setup. Find starfish for sale, supplies and equipment at your neighborhood Petco.
Updated on November 13th, 2025
Everything you need to know about how to start a fish tank. Learn about setting up an aquarium, choosing the right type, and acclimating new fish to your tank.
Updated on November 13th, 2025
Thanks for your question about your fish, and congratulations on your new family members! I didn't see how recently the tank was set up, but there are a couple of things that could be going on. I would start by checking your water quality - any abnormalities in water quality can make fish have abnormal behaviors, and the water looks a bit murky in the photos you provided. There may be parameters that need to be addressed depending on what you find. If you do not have a water quality kit, they can be purchased at the pet store or an aquarium store, or you can take a sample of your water in for evaluation to these places as well. Some will charge a small fee for this service, just so you are prepared. Also, with recent tank set ups, it can be stressful for fish as they are in a new habitat. I would recommend keeping the light on for only a few hours per day to start, as the bright lights can be shocking for them (since fish don't have eyelids). Gradually you can increase the length of t
Updated on August 12th, 2025
Thanks for reaching out about you fish. It is believed to be a Comet goldfish. Water quality and nutrition is the key to success. Testing water parameter for pH, ammonia, nitrite and nitrate will give you guidance for a healthy environment. Purchased food should be rotated out every 3 months as vitamin C and other nutrients degrade over time. Trying to maintain water temperature can be challenging with out a heater, but most fresh water fish tolerate some changes. Good luck.
Updated on August 12th, 2025
Like any creature moving into a new habitat at first they will be wary and nervous. I would give the fish a bit if time to settle in and become acclimitised to the new tank before worrying too much. If you try and not disturb them overly you will find that they gradually become more comfortable and start to explore the tank.
Updated on August 12th, 2025
It looks like a species of gourami. Most can be kept in a community tank with other fish. The black may be caused by high ammonia levels. Submit a water sample for testing or use a liquid home test kit to check chemistry. Ammonia can kill fish if levels are high enough. Partial water changes can be done daily to stabilize chemistry and maintain water quality. Use only aged or conditioned water that is temperature matched to prevent further stress or shock. My preferences for water conditioners include AmQuel Plus, NovAqua and StressCoat.
Updated on August 12th, 2025
Check the water chemistry. Two goldfish can quickly overwhelm a tank with their large bio load. Aim for 0.25 ppm (parts per million) or less ammonia, 0 ppm nitrites and 40 ppm or less nitrates with a temp between 65 and 72F. If water chemistry is good, it is possible the red marks are from the pleco. They are notorious for sucking the slime coat off goldfish leaving red marks and wounds. Partial water changes, 30-50%, using aged or conditioned water that is temperature matched are safer and less stressful than complete changes. Give the antibiotics time to work. You can add in plain aquarium salt (NOT table salt) to aid healing. Dissolve one teaspoon per gallon of water in a cup of tank water and gently pour it in the tank. Perform partial water changes after 10-14 days to reduce salt content.
Updated on August 12th, 2025