Can Aquarium Fish Survive in a Pond or in A Lake

By Eddie Waithaka @aquariawise

Can Aquarium Fish Survive in a Pond or in A Lake

If you love keeping fish as much as I do, I’m sure you’ve considered having some in a pond, more so if you have a big compound and crave the sight of colorful fish that are a little too big for an indoor aquarium.

You may also have some fishes like plecos, which can grow quite big and if you dint know this before you got them, they may cause you problems.

You will want to keep the fish but won’t have enough room for it in your tank.

So, is it possible to keep aquarium fish in a pond?

Will they survive?

Well, some aquarium fish will survive in a pond, but some will likely end up dead in a shorter time than they would if they lived in an aquarium.

Aquarium fish, especially those purchased from commercial breeders, are accustomed to a closed, controlled environment.

Water temperature, quality, and chemistry are monitored closely by the owner, something that doesn’t happen for fish kept in ponds.

Moreover, most fish kept in home aquariums are tropical fish native to equatorial waters, which varies significantly in chemistry and temperature from water in temperate regions, meaning only a small number of fish will survive in this environment.

Given this background, a few ornamental aquarium fish I would consider adding in a pond include koi, white cloud minnows, catfish, livebearers, and goldfish

Also note you’ll have more success keeping aquarium fish in a pond if you live further South in the USA or the tropics elsewhere in the world.

Can You Release Aquarium Fish in A Lake

Many people have a fish that gets too big for their aquariums.

They don’t want to kill it since it has been a pet to them, and without a pond in their yard, they release it into natural environments such as lakes.

However, most people don’t know their ornamental fish species will likely not survive in wild water, more so tropical fish released in temperate lakes.

While some species might hang on and even reproduce, most will succumb once winter rolls up.

Tropical fish can’t survive winter water temperatures in a temperate climate.

Besides, if you have an ornamental fish you can’t have anymore, there are better ways to rehome it than releasing it in a pond, lake, or fountain.

These places are not natural homes for ornamental fish. The fish can harm the unique local ecosystem almost as much they can get harmed.

That said, you are better off starting a tub pond in your backyard for large fish that won’t fit in your tank or offer them to your local fish store for resale gifting to able deserving customers.

What Kind of Fish Can Live in an Outdoor Pond

Essentially, any fish living in a closed environment, whether a pond or aquarium, only needs the setting to be ideal for it.

You’ll note some species are hardy than others, but overall, they all do best in an environment akin to what they are used to in the wild.

Koi, goldfish, and white clouds tolerate unheated tanks and may do well in outdoor fountain ponds, even inside sub-tropical waters. Mollies, guppies, platys, and swordtails are pretty hardy and prolific breeders as well, so they might be worthy candidates.

Unfortunately, that is almost as far as they go.

Most of the other species are as tropical as they come, so you will only find better success if you live in an equatorial climate, where the Winter and Summer temperatures don’t vary too much.

The temperature must remain over 65 degrees Fahrenheit at night and above 72 degrees in the daytime.

That said, if you are willing and have enough space to move your fish indoors during the winter months, then you can try more tropical fish species in your pond, including plecos and catfish.

Make sure you only pair fishes that won’t prey on each other in your pond and preferably species that prefer similar water parameters.

Below is a list of the fish you should consider if you decide to go down that road.

What Kind of Fish Can Live in an Outdoor Pond UK

I believe any place in the UK is almost as subtropical as it gets, meaning you might not have much success keeping tropical fish in your outdoor pond.

You can try koi and goldfish since they are not tropical species per se.

They can handle a little cold, though, during winter, you may want to move them inside or figure out a way to insulate your pond.

If you are not thinking of strictly aquarium fish suited for ponds, a dozen native species will also survive in a pond in the UK, including gudgeons, barbels, rudd, roach, and bream.

Even so, you need to be cautious because some species, although common, are illegal to keep.

How Do You Keep Fish Alive in an Outdoor Pond

Keeping fish alive in a pond is a lot like maintaining them in an aquarium, only that you’ll have to deal with harsher external perils.

Everything from water quality, aeration, plants, and feeding, should be done with particular adherence to the species of fish you are keeping.

You also need to pay a lot of attention to your pond temperature during winter. As we saw before, the temperature needs to remain between 65 and 72 degrees Fahrenheit.

Another challenge you may come across is the amount of dissolved air in your pond. You do not want an environment that will suffocate your fish, so add a submersible aerator, especially when you do not have plenty of live plants.

A pond with a fountain waterfall is also better aerated, so if you can, add this feature since it’s good for beauty as well.

Since Ammonia from fish waste, decaying plants, and leftover food is a problem in ponds the same way it is in aquariums, you may need to add a filter in your pond.

It should be able to remove all biological, chemical, and solid-detritus, perhaps better than you would need to in a fish tank. The reason being, a pond is exposed to a lot more dirt than an indoor aquarium.

Now, if you live in sub-tropical regions where the average outside temperature remains relatively low, there is only a limited number of fish you can keep.

Essentially, only koi and goldfish would do best in your situation. You can try catfish and other bottom dwellers since the water at the base of the pond remains relatively warm throughout the day.

The best part about adding bottom feeders like common plecos, weather loaches, and siamese algae eaters in your pond is they will keep the bottom clean and free of algae, the same way they do in fish tanks.

In conclusion, if you are looking to release your finnies into a local pond or lake, you perhaps should first consider offering to other aquarists around your local area. Many fish stores will also accept your fish if they have space.

The only agreeable reason for moving your aquarium fish is if they outgrow your fish tank or you can no longer have them in your house for whatever reason.

And even then, you should relocate them to you a pond or one which you know the owners, and you’re confident they’ll give you adorable finnies the best care.

Im not sure if this is the case everywhere, but in my local area, commercial feed breeders will accept fish that need a new home. Try contacting a few in your area, see what they have to say.

If you are located in the USA (more so Florida) and are looking to buy tropical (freshwater ) mentioned in this or any other post (and more), check out Consolidated Fish Farms Inc.

Also Consider usingAquariawise Coupon Code for a 10 percent discount on eligible purchase. They are a great source for healthy aquarium fish, plus we get a small commission with no extra cost to you.

That’s all for this post.

Good luck finding a home for your finnies🐠🐟.

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