Introducing a New Goldfish to a Tank

Introducing a New Goldfish to a Tank

common goldfish swimming
The best way to transfer a new goldfish into its new home is to leave the fish in the oxygen and water filled bag that the pet store employee put your new pet into. Simply place it directly into the goldfish bowl or tank and wait until the water temperatures are equal. Don’t forget about it in the bag since it only has so much oxygen and If you leave it in there too long, it will likely suffocate and die. When the water temperatures are equal (30 to 45 min), carefully release the fish and the bag water into the new tank. mixing the two bodies of water is a good idea because it acts as a buffer for shock. Depending on where you bought your goldfish from, you might want to consider a quarantine tank.
floating goldfish bag
Only add a new goldfish to your existing aquarium or pond if it has the required space your goldfish needs. If you overstock them, it will lead to poorer water quality and require you to perform maintenance more often. Get more information about this by reading the next beginners post, How to Clean a Goldfish Bowl.

Transfer a Goldfish from a Tank into a Pond

If you want to transfer an indoor fish outdoors, do it slowly over the course of a week or so. Slowly bring the water temp in the aquarium down to that of the outdoor garden pond. Mix in some of the pond water into your tank with the goldfish. The key here is to not shock them with rapid changes in water parameters. Yes goldfish can live in both warm or cold waters but any fast temperature change will likely kill them. Slowly mixing in the pond water will also help with the transfer. Read more on this topic in goldfish water temperature extremes.

Reviewed By: Tim Winter

Tim Winter has a strong affection for pets and wildlife. His years of experience caring for various types of pets has led him to share his knowledge with others on the best practices in pet care. Tim holds a Bachelor of Science from the University of Oregon School of Journalism and Communications.

23 thoughts on “Introducing a New Goldfish to a Tank”

  1. I got 2 fantail goldfish the first day all they wanted to do is lie at the bottom. Is that normal they seem a little happier today

  2. I won 2 goldfish from the fair in sept still going strong been thinking of getting 2 more will they be OK if I do? The bowl that they are in as about 6 gal of water in would that be OK

    • It would be okay but only for a very short period. As these goldfish grow, you need a much larger tank. Also, with additional fish, you will need to change the water more regularly. If you can commit to getting a larger tank and are open to changing the water a few times a week, then you could probably get more fish. Note that one adult fully grown common goldfish needs about 10 gallons to stay healthy.

      • 10 gallons per inch of fish
        Dechlorinate your water
        Change 1/2 the water weekly
        Need a filter and aerator

  3. I won a goldfish a fair (but the fish werent treated cruelly). I put them in a bucket for now with some new tap water and their old water. How can I introduce them to a proper tank? Thanks!

    • i won my fish at the fair, i just put him in a bag and left the bag in the tank for 2 hours. then i let him out of the bag and he settled nicely into his new home, ive had him almost 2 months and hes still alive, im going to be buying a friend for him soon as i have just upgraded him into a bigger tank

    • Hello Abby

      Your Aquarium shop should sell a decent starter tank with a filter to keep him healthy.

      Change water every few days and dont overfeed him.

      Good luck

    • sme way, put them in a bag in the tank , then when the water is the same as the tank temp gently release them into the new tank along with thier bagged water

      • Within 15 minutes water temp needs to be the same. Introduce the new water half cup at a time. Do not throw the bagged water in their; because it will contaminate the water; the fish; and the fish in the aquarium.

Leave a Comment