Koi Fish Costs, How To Feed Them, How Long They Can Live, And More

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Koi Fish Costs, How To Feed Them, How Long They Can Live, And More

Here Are The Answers To The Most Commonly Asked Questions About Koi And Pond Fish

Thank you for caring enough about your fish (or soon-to-be fish) to look up how to best care for them.

In this post, you’ll discover if fish increase your workload, how and when to feed them, how to care for them during winter, their cost, which and how many fish you can put in your pond, how to protect them from predators, and if they eat algae.

We Can’t Yet!

“Why can’t we go buy koi fish right now?” asks Adam.

“Because we have no idea how to properly care for them,” answers Angela. Adam frowns a bit, cocking his head. “We put them in the pond and feed them fish food sometimes, what else is there?”

“Um, maybe, their cost, how many we can put in our pond, how to protect them, if they make it more work for us, and there’s probably more,” says Angela. “Not to mention knowing what kind of diseases fish can get.”

Adam’s frown turns into surprise. “I didn’t think of any of those things. You have some good points. Ok, let’s get on Google and see what we can find.”

The couple brings their phones out and starts doing some digging.

Here’s what they end up finding:

1. How Much Koi Fish Cost

Koi fish can cost anywhere from $10 to $20,000. It depends on their size, shape, and coloring. Koi can grow to over 3 feet long. The favored shape is torpedo-like. There are also many patterns and colorings to choose from.

The bigger, brightly colored, well-shaped koi will cost the most.

2. Do Koi Fish Make Owning A Pond More Work?

Not really (surprising, right?) We create ecosystem ponds and fish make up about 20% of a naturally balanced, holistic, organic ecosystem.

Koi fish help you enjoy your pond more by:

  • Helping control insects by eating them and their larvae
  • Keeping plant and algae growth in check by snacking on them
  • Helping fertilize plants with their waste
  • Adding color and movement to your pond
  • Making great pets

3. How Long Koi Fish Live

Japanese koi fish can live between 40 and 60 years. For non-Japanese koi fish, the average life expectancy drops to 15 years. This huge difference mostly comes down to genetics and diet before being sold.

4. How And When To Feed Pond Fish

Learning how to feed koi fish is easy. With our ecosystem ponds, you don’t have to feed your fish. They can live off of plant matter, algae, and insects. You can feed them fish food and most healthy human foods every so often.

You can feed your fish as much fish food as they can eat in 5-minutes 3 times a day. Cleaning any leftovers out helps keep the water clean and clear of algae.

For the sake of your fish, do not feed them when temperatures hit 50 degrees Fahrenheit and lower. They start hibernating at this temperature. This means their bodies won’t digest any food, leaving it stuck inside them for months.

5. What To Do With Your Pond Fish In Winter

With our ponds (or any that are 2 feet deep or more) you don’t have to do much of anything to care for pond fish in winter. The water will freeze on top and your fish will hibernate near the bottom.

You’ll want to keep a hole in the ice so oxygen can get in and your fish’s, *ahem*, gases can escape. Move any aerators to the shallow end. Don’t want to mix the cold water with the warm water!

6. What Fish Can Go In A Koi Pond

Goldfish and koi fish are the best for koi ponds. There are many types of koi and goldfish, so you have a wide variety of looks to choose from.

7. How Many Fish Can You Put In Your Pond

The general rule of thumb we suggest is 1-inch of fish per square foot of pond surface area. In other words, a 10’ x 10’ pond, which is 100 square feet, could support 100 inches of fish. This 100 inches could consist of 10 ten-inch fish, 20 five-inch fish, etc.

You can also use the how many fish per gallon rule.

Too many fish means too little food, can lead to health problems, and can lead to an overgrowth of algae. Too few fish means you’ll have to use more filters to keep your pond water clean and clear.

8. Protecting Your Fish From Predators

There are a few different ways to protect your pond fish. They include installing fish caves, fish tunnels, floating plants, and more.

9. Do Fish Eat Algae?

Yes, pond fish do eat algae! They’re a natural, living filter that helps keep the water clean and clear (for the most part, they do still create waste). They work with other filters in your pond to keep algae from growing too much.

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“Now we can go get some fish for our koi pond,” says Angela. Adam nods and smiles. “How about you drive while I keep digging for more information? Want to make sure we’ll be great fish owners!”

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