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Why is my goldfish staying at the bottom after moving to a new tank?

Updated on September 23rd, 2025

Pet's info: Fish | Unknown - Fish | Male

I changed my goldfish to new tank, and now he's staying on the bottom and not swimming around. When I go up to the tank he try's to move around. It's like he can't swim

4 Answers

Most Helpful Answer

Answered By Dr Stafford, BVetMed, MRCVS

Veterinarian

Published on June 17th, 2017

Hi there, when you change a tank over you should take some water from the previous tank then make it up with freshwater. You should let this stabilise for one week before adding the fish. If you put a fish straight into a new tank without letting the water acclimitise it can be a shock to it's system. At this point all you can really do is let the fish settle in and don't disturb its tank for a week or so.

4Pet Parents found this answer helpful

Related Answers from Veterinarians

Answered By Angel Alvarado, LVT
Licensed Veterinary Technician
Check the water temperature. Goldfish are cold water fish but if the water is too cold, it will affect activity. Aim for a temperature between 65 F and 72 F.
A sudden change in water temperature can cause shock which may affect his movement also.
1Pet Parents found this answer helpful
Answered By Todd Cecil
Veterinarian
Published on February 26th, 2019
Thanks for reaching out about your goldfish. If multiple fish are involved, water quality, infectious diseases, and toxicities should be considered. Once again, test water quality for pH, ammonia, nitrates, and nitrates. Correct any concerns. Water temperature should be monitored and adjusted.
If these things are fine, a veterinary visit is needed to provide further answers.
Good luck.
1Pet Parents found this answer helpful
Answered By Angel Alvarado, LVT
Licensed Veterinary Technician
Published on April 6th, 2017
It may be the pH change or other change in water chemistry. Use a home test kit to check water quality. Make adjustments as indicated.
It may also be a response to a temperature change. Check water temperature and increase the heat if necessary, just don't forget to turn it down or off once the temp is within range.
2Pet Parents found this answer helpful

Smart Picks for Smart Questions

Related Questions

Health & Wellness

Why is my goldfish not moving and staying at the bottom of the tank?

Since the others in the tank are behaving normally, this one may be sick or injured. Ideally, it should be separated into a quarantine or hospital tank Check water chemistry first, even if you've done it already. You can use a 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 (0ppm) of ammonia and nitrites, with nitrates at 20ppm or less. Perform partial water changes to correct or stabilize water chemistry. Use only conditioned water that is temperature matched to prevent additional stress or shock. Goldfish are cold water fish and do best between 68F and 74F. Change no more than 30% of the volume at one time. In the absence of other symptoms or injury, medications cannot be recommended. You can use plain aquarium salt (NOT table or Kosher salt) as a general tonic to decrease stress, increase gill function and aid in recovery. Dissolve 1 tablespoon of salt per 2 gallons of water in a cup of tank water and gently pour it into the tank. Treat for 10-14 days then perform partial water changes to decrease salinity.

Updated on September 23rd, 2025

Why is my goldfish at the bottom, bent, not eating, and struggling?

Goldfish sit at the bottom of a tank when they are not well, often because toxins have built up in the water. Goldfish are usually active, and lethargy is a sign of illness. Maintaining good water quality is essential for proper aquarium care. In the enclosed, finite space of a fish tank, toxic elements, such as ammonia and nitrates, can build up in the water causing disease and killing fish. The only way to detect and control toxins is to perform regular chemical tests on the water and to perform gradual water changes to remove impurities and maintain the proper water parameters.

Updated on September 23rd, 2025

Why are my new goldfish gulping at the top and tank water is green?

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 September 23rd, 2025

How do I safely move my goldfish from a bowl to a larger tank?

As log as she is acclimated to the water temperature, she should be fine. Place her in a bag of water and then float the bag in the tank for 20-30 minutes. You can then scoop her out with a net and place her in the new tank. Confirm proper chemistry of the new tank 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. Aim for 0 ppm ammonia and nitrites with nitrates at 20 ppm or less. pH should be around 7 and water temp should range between 65 F and 72 F since goldfish are cold water fish.

Updated on September 23rd, 2025

Food & Nutrition

My new Glofish are hiding and staying at the bottom. Is this normal?

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 time that the lights are on so that you reach a cycle of 10-12 hours of light and 12-14 hours of darkness for them. I hope this gives you a place to start, and I wish you and your mom the best with the new pets!

Updated on September 23rd, 2025

Training & Behavior

Why is my new goldfish at the bottom of the tank and not eating?

There are a few possibilities including normal adjustment or something wrong with the water quality. Also, you will need a bigger tank for Nutty that includes a filtration system. Here is a link about goldfish care: https://www.petcoach.co/article/how-to-help-your-new-goldfish-thrive/ https://www.aqueon.com/information/care-sheets/goldfish Make sure the water quality is good for Nutty. I hope this helps and please feel free to post any additional questions.

Updated on September 23rd, 2025

Health & Wellness

Why is my fish agitated and swimming frantically after a water change?

Did you change any of the plants or other features in the tank? That could be confusing him. It could also just be due to stress. Did you take him out while you changed the water or did you leave him in? Taking him out is recommended but it can still be stressful for him due to all the moving. Did you do a partial water change or a full change? Since I am not sure of what your procedure was it is hard for me to comment. I suggest you refer to this article about how to properly change the water to make sure you are doing it correctly. If you still have more questions please feel free to post again. ( https://goldfisho.com/goldfish-tank-water-changes/ )

Updated on September 23rd, 2025

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