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Trying to take care of a goldfish is one of the great shared experiences of pet lovers everywhere. No matter who you are or what your background might be, there’s a decent chance you’ve tried to take care of a goldfish before.
That said, there’s a big difference between trying to keep a goldfish afloat in a tank and trying to do the same in a pond. It isn’t as though there are a whole host of kindergarten classes taking turns taking care of goldfish as they swim along in passive ponds.
But just how hard is it to take care of goldfish in ponds, and do those ponds require pumps?
Optimal Conditions for a Goldfish
First, let’s take a closer look at the conditions in which goldfish are usually kept and those they require to lead a happy, healthy life.
Goldfish are typically considered to be “cold-water fish” and can thus be kept in normal ponds or aquariums so long as they are somewhat heated to keep them from freezing. These fish thrive best in water that is kept at around 68° to 74° F.
The pH level isn’t too critical for goldfish. That’s part of the reason they are a lot easier to take care of than many of the most finicky aquarium fish.
Still, your goldfish will do best in water that is kept at somewhere between 7.0 and 8.4 pH.
Goldfish are omnivorous, and so they can eat everything from a few flakes to some vegetation to crustaceans and insects.
Goldfish in Ponds
If you are going to keep your goldfish in a pond, there are a few things you’ll want to keep in mind.
The big thing with goldfish is stability. They can put up with a lot, but nobody likes having to deal with a lot all at once.
As such, whether you keep your goldfish in an aquarium or a pond, you should endeavor to keep conditions as steady as possible. Do not change the conditions in the aquarium or pond too quickly.
If you add sea salt to the pond or aquarium, about five gallons’ worth should suffice.
Despite the commonality of the image of a goldfish swimming along in a bowl, your goldfish will actually be a lot happier swimming in a pond or properly-adorned aquarium.
One reason for this is the fact that goldfish can grow larger than you might expect – up to six inches. While your goldfish probably won’t get anywhere near that size, it may still be big enough to feel cramped in a typical goldfish bowl.
Another reason why goldfish bowls simply won’t do is the fact that they lack the hiding places, plants, and other accoutrements that are necessary to keep goldfish happy. These can easily be added to a pond.
That said, fancy goldfish can accidentally cut themselves or see their scales damaged when they brush up against sharp plants or fixtures, so be careful about the plants and pond or aquarium decorations you give them.
The size requirements for a goldfish are at least 20 gallons per fish, which is also easily met by placing them in ponds.
Goldfish get along well with most other fish, which is another reason why they work well in ponds. You can plop them in your koi pond and not have to worry about them getting into fights or bullying other fish.
The Question of Pumps
You do not need pumps for the temperatures at which goldfish thrive. As such, you can potentially keep them in a pond without pumps.
Whether you should do so, however, is a more complex question.
For one thing, you’ll have to keep in mind what we said earlier about goldfish preferring consistent conditions. If you live someplace where the weather is the same day after day and week after week, you should be fine.
However, if you live someplace where the weather is more variable and don’t install pumps, you may find yourself struggling to keep the water at a comfortable temperature for your goldfish.
It’s worth noting that goldfish can grow larger in ponds than they tend to in aquariums, often reaching a size of 6 to 10 inches.
That said, your goldfish will require a lot of filtration, which is another reason why they are often kept in ponds with pumps. Goldfish can be sensitive to ammonia buildup and other issues with water that has not been properly pumped and filtered.
Ideally, you should test the water in your pond every day.
You’ll also need to make sure you do your best to limit the amount of algae you have in the pond.
Then there is winter. As mentioned, goldfish can be kept at temperatures that are cooler than some other aquarium fish, which is one of the reasons why they are easier to keep in a pond (even one without a pump) in the first place.
That being said, unless you live somewhere that stays hot year-round, when winter rolls around you’ll probably need to take your goldfish out of their pumpless pond.
In fairness, some people put in a lot of effort to keep their goldfish alive in a pumpless pond even in wintertime, going so far as to poke holes in a frozen-over pond so as to place heaters in them.
However, it’s a lot easier to either install a heater-pump combo from the get-go or simply take your goldfish out for the winter.
An even bigger problem with keeping goldfish in ponds without pumps is the fact that they can produce a lot of waste, and that isn’t going to go away by magic. Either you pump that waste out, you expend a lot of effort getting rid of that waste yourself, or you simply let your goldfish wallow in their own waste as the pond starts to smell worse and worse, which isn’t pleasant for anyone.
Some plants can help you clean that waste. They dissolve nutrients into the water while combating algae, though how well they are able to do this will obviously depend on the type of plants you have.
The more plants you have in your pond, the better the oxygen quality will typically be.
The amount of sunlight can impact your ability to keep goldfish in ponds without pumps in a couple ways.
On the one hand, more sunlight often means more heat, and that can make it easier to keep your goldfish at a comfortable temperature in the absence of a heating pump.
On the other hand, however, more sunlight can also mean more algae.
There is often a big difference between what you “can” and “should” do in life, and keeping a goldfish in a pond without a pump is yet another example of that dichotomy in action.
It is possible to keep goldfish in ponds without pumps. A combination of sunlight, a naturally-warm environment, and plants can help with the heating and filtration aspects of fish care, making this arrangement theoretically possible and even potentially comfortable.
However, there is a big difference between theory and practice, and in the latter case, keeping goldfish in ponds without pumps is often simply too big of a hassle. It is far too easy for the fish to get cold or the waste to start to build up.
In the end, unless you are extremely dedicated to making this work, it is probably better to just get a pump for your goldfish pond.