How to Get Free Pet Fish Safely in the United States
To get free pet fish safely in the United States, make sure your own tank or pond is cycled and big enough first, ask the owner why the fish are free and how long they have been healthy, and see the fish in their water before you take them. Then move them in insulated, well-packed bags and quarantine them before they join any fish you already have.
Free fish are often a fair deal: owners give away livebearer fry, goldfish or koi that outgrew a tank, or a whole setup before a move. The fish may cost nothing, but the equipment, the upkeep and any disease you bring home do.
Key points
- Free fish still need a cycled tank or pond sized for their adult size.
- Good reasons for free fish include moving, too many babies or a fish that outgrew its tank; recent deaths are a warning.
- Look for white spots, clamped fins, gasping and dead fish in the same tank.
- Quarantine new arrivals for several weeks and never share nets between tanks.
- If you cannot keep them later, rehome them; never release fish outdoors.
Why do people give pet fish away for free?
- Too many babies: guppies, platies and mollies breed readily, and owners give away the extras.
- Fish that outgrew their tank: PetMD suggests about 20 gallons per goldfish and about 250 gallons per adult koi, so owners of small tanks run out of room.
- Moving house: a full tank is heavy and hard to move, so owners often give fish away with the equipment.
- A change of hobby or less time for tank care.
These are fine reasons. Be more careful when the owner mentions fish that keep dying, a tank they want to empty quickly, or fish they cannot identify.
On PetzLover you can browse free pet fish listings and save the search to get an alert when someone near you posts one. Free fish are almost always offered for local pickup.
What does a free fish really cost?
The fish are free, but the setup is not. Plan for these costs before you say yes:
| Item | Typical cost | Notes |
|---|---|---|
| Basic 10-gallon freshwater setup | Around $170 to $200 | Tank, filter, heater, light, conditioner and test kit |
| Quarantine tank | About $60 for a 10-gallon tank, plus a $20 to $50 filter and a $25 heater | Keeps new fish apart for several weeks |
| Yearly upkeep of a small tank | About $300 to $500 | Food, test kits, filter cartridges and conditioner |
The figures are from a 2026 US cost guide by The Vet Desk and vary by region. If a used tank comes with the fish, check for leaks, cracked glass and a working heater and filter, and ask the owner to send the filter media with the fish, kept wet in tank water, so your tank starts with its bacteria.
Koi and pond goldfish are a bigger commitment. PetMD says koi typically live 25 to 50 years, and they need a filtered pond rather than a tank.
What should you ask before taking free pet fish?
- Why are you giving them away?
- What species are they, how old are they, and how big are they now?
- What temperature do you keep them at, and what do they eat?
- Any deaths, white spots or medication in this tank in the last month?
- Are they peaceful, or do they fight or eat smaller fish?
- Can I see them in their tank before I take them?
- Is any equipment included, and does it work?
Make sure the species is legal where you live. Snakeheads are federally listed injurious fish, and states restrict others; California, for example, restricts piranhas, snakeheads and gars. If you are not sure what a fish is, do not take it until you know.
What are the red flags with free fish?
- White, salt-like spots (ich), fuzzy patches, ulcers, cloudy eyes or a swollen belly.
- Fish gasping at the surface, rubbing against objects or sitting clamped on the bottom.
- Dead fish in the tank, or an owner who says fish keep dying.
- Cloudy or foul-smelling water.
- An owner who cannot tell you the species.
- Anyone asking for a deposit or a shipping fee for free fish.
CDC's checklist for healthy fish applies to free fish too: active fish that swim normally, with smooth, shiny scales that are not discolored, no bumps and intact fins.
How do you move free fish home safely?
- Have your tank ready, with the heater set and the water tested, before you collect.
- Bring an insulated cooler or foam box and spare bags.
- Bag fish in their own tank water, about a quarter to a third water and the rest air or oxygen, and double-bag.
- Drive straight home and keep the cooler out of the sun.
- Float each bag in the quarantine tank for about 20 to 30 minutes, then net the fish in without the bag water.
Quarantine for several weeks before mixing with your other fish. Hobbyists commonly use 3 to 4 weeks, and VCA advises at least 30 days after an ich outbreak. Do not share nets, buckets or plants between tanks in that time.
Is a free fish right for you?
Say yes when you have the space, the species suits your tank and the fish look healthy. Say no when the fish will outgrow everything you own, or when you are not ready for a long commitment: goldfish can live 10 to 15 years, and koi for decades.
If you would rather choose specific fish, read how to buy pet fish. If you are taking over a whole established tank, how to take in rehomed pet fish covers the handover. Owners giving fish away can read how to give away pet fish for free without risk.
Frequently Asked Questions
Where can I find free pet fish?
Owners who are moving, hobbyists with too many babies and people with overgrown goldfish or koi often give fish away. Check local listings, aquarium society meetings and koi clubs. Collect in person so you can see the fish first.
Are free fish usually healthy?
Many are, but you cannot tell without seeing them. Look at the whole tank for spots, gasping or dead fish, and ask about recent treatment. Quarantine them for several weeks before they meet your other fish.
Do free fish need a cycled tank?
Yes. Fish added to an uncycled tank face ammonia and nitrite while the filter bacteria grow, which takes about 4 to 6 weeks. If your tank is new, ask the owner for some of their filter media or wait until your tank is ready.
Can I take free koi for my pond?
Only if the pond is large enough, about 250 gallons per adult koi, with filtration and aeration. The Merck Veterinary Manual suggests quarantining new koi for at least 30 days at about 75°F because of koi herpesvirus. Ask the owner whether any koi died recently.
What if I cannot keep the free fish after all?
Rehome them to another hobbyist, an aquarium society or a store that accepts fish. Never release them into a pond, lake or stream, where released fish can spread disease and harm native wildlife.
Should I pay anything for free fish?
Not a deposit or a shipping fee. Bring your own bags and cooler. If the owner wants a small amount for equipment, see it working before you pay.
Helpful guides
Pet for FreeHow to Give Away Pet Fish for Free Without Risk in the United StatesGive pet fish away safely by screening for a cycled tank, checking the species is legal for the new owner, packing fish properly and never releasing unwanted fish outdoors.
Pet for SaleHow to Buy Pet Fish in the United StatesBuy pet fish in the US by choosing species that fit your tank or pond, cycling the water for 4 to 6 weeks first, checking that each fish is active and clean, and quarantining new arrivals.
Pet for SaleHow to Sell Pet Fish in the United StatesSell pet fish in the US by confirming the species is legal for you and the buyer, listing only healthy fish with honest details, screening buyers on their setup and handing fish over bagged and ready to travel.
Pet for RehomingHow to Take In Rehomed Pet Fish in the United StatesTaking in rehomed fish means asking about their history and water, preparing a cycled tank or pond sized for adult fish, moving them carefully and watching closely through the first few weeks.
Pet for RehomingHow to Rehome Your Pet Fish Responsibly in the United StatesRehome pet fish responsibly by describing their health, size and needs honestly, screening for a suitable tank or pond, handing over in person with care notes and never releasing fish outdoors.