Wonder Contributors

November 1 is National Family LiteracyDay. What better way to celebrate the WONDER to be found in families reading and learning together than to feature a brand-new Wonder of the Day inspired — and written — by a family who loves to Wonder. Today’s fishy Wonder of the Day comes from author Monica Holloway and her 15-year-old son, Wills. Wills raises fish in three freshwater tanks that he maintains daily. He’s currently busy tending to 22 black-and-white Mollies that were just born!

If you’re fascinated by aquariums like we are, you might have WONDERed whether the fish in aquariums swim in freshwater or saltwater. As it turns out, aquariums can be filled with either freshwater or saltwater. It just depends upon what kind of fish you want to raise.

There are thousands upon thousands of different types of fish all over the world. Some live in freshwater, such as rivers and lakes, while others live in saltwater oceans. If you want to raise fish in an aquarium, you need to create an environment for them that’s similar to their native environment.

You can get a variety of different kinds of fish at a local pet store or exotic fish store. Freshwater fish frequently come from farms where they are raised to be sold in pet stores. Some popular types of freshwater fish include Bettas, Angelfish, Goldfish and Rainbow Fish.

Saltwater fish tend to be wild fish from the ocean imported from all over the world. Saltwater fish require a special environment that includes consistent temperature and water conditions. Oceans, because of their size, tend to stay the same most of the time and change very slowly, if at all.

To mimic ocean conditions in an aquarium, it’s often necessary to use a larger tank that can hold more water. You also have to keep a close eye on the tank’s water conditions to make sure water temperature and chemical levels remain constant.

Some popular saltwater fish varieties include Lionfish, Clownfish, Seahorses, Eels, Groupers and Angels. Angels, for example, are very beautiful, but they can be very difficult to raise because they are sensitive to even the smallest changes in water quality.

With the proper care, though, Angels can live up to 10 years. Just be careful when choosing neighbors for Angels. They get along well with other species, but they don’t like other Angels!

Raising fish in an aquarium can be a rewarding hobby that provides countless hours of enjoyment. It’s not always an easy task, though! Aquariums require daily maintenance.

Like all animals, fish require regular feeding. You will also need to monitor the temperature and quality of the water to make sure you’re providing a quality home for your fish. And like your room, aquariums need to be cleaned on a regular basis to make sure you maintain a safe environment where your fish can flourish!

69 Join the Discussion

1 Star2 Stars3 Stars4 Stars5 Stars  (29 votes, avg. 3.79 out of 5)
  1. We thought the angel fish was colorful and pretty. We also thought the mollies were beautiful. Some of the students in our class have fish tanks at home.

    We think tomorrow’s wonder is going to be about loving school, having fun, pople who wonder.

    • Hey there, Wonder Friends in Ms. Bayko’s Class! Thank you for pointing out your favorite parts of today’s fish Wonder. We think it’s pretty cool that some of our Wonder Friends have their very own fish tanks at home. How often do you have to feed your fish?

      All our friends at Wonderopolis hope you have a terrific Thursday– and we will see you tomorrow! Thanks for sharing your super guesses! :)

  2. We liked today’s WONDER and thought it was cool that a Wonder Family wrote it!

    We think tomorrow’s wonder could be about Alice in Wonderland, Wondering, Wonder Pets, the book Wonder, or maybe even how your brain wonders.

    • Hello Wonder Friends in Mrs. Ski’s AM class– it’s nice to see you today! We hope you had a great time trick-or-treating last night! :)

      Today’s Wonder is really exciting… do any of you have pet fish at home? We really enjoy when other Wonder Friends help us create the Wonder of the Day®! Did you know today is National Family Literacy Day? We think you’re in the right place– especially on this special day! Thanks for sharing your SUPER guesses for tomorrow… have a WONDERful day today and we will Wonder with you soon! :)

    • Thanks for sharing your SUPER comment, Hailey! We think the video lets us take a peek into the life of our fish friends! Do you have a favorite fish from today’s Wonder? :)

  3. I like to see all those pretty fish on that video… my favorite color is neon green just like that big fish. Please reply. :)

    • WOW, how cool that one of the fish was sporting your favorite color, Anthony! We bet it takes a lot of patience to care for all those fish, but they seem like they are enjoying their time in the aquarium! Do you have a favorite fish, Anthony? :)

  4. We really enjoyed today’s Wonder. Many of us have or have had fish as pets. We wondered about what kind of fish we’d like to have in our aquariums- goldfish or clownfish (depending on if it was freshwater or saltwater!)

    We think tomorrow’s Wonder will have something to do with thinking, or a superhero named Wonder Man or Wonder Woman!

    • Hey there, Third Grade All-Stars! We think its pretty cool that some of you have had an aquarium of your own– we bet you are WONDERful at taking care of your amphibian friends!

      If we had an aquarium at Wonderopolis, we think we’d want to have fish who get along with all types of fish friends. Like you said, it would depend on the type of environment they can live in!

      Thank you for sharing your SUPER guesses for tomorrow’s Wonder of the Day®… we hope you have a terrific Thursday! :)

  5. I love fish! My family used to have two, but they died. I thought the fish were really pretty!! Way to go!! Thanks!
    =Bryleigh= :D

    • Very cool, Bryleigh! We’re sorry to hear that your fish are no longer with your family, but we bet you had a great time caring for them! We enjoy all the different colors in the video today, too! Thanks for sharing your great comment today, Wonder Friend! :)

    • We’re so happy that today’s Wonder was right up your alley, Gage! Fish are so much fun to Wonder about… there are so many different kinds that our heads are swimming! Thanks for commenting about today’s Wonder– we hope you have a totally awesome Thursday! :)

    • Oh no, we’re sorry to hear that Michael! Sometimes viewing a video from school or a public place will cause video issues– we Wonder if you can try again at a later time today, or on another computer?

      We hope you enjoyed reading today’s Wonder… we are excited to use our imaginations with you! :)

    • We certainly agree with you, Payton! Today’s Wonder was lots of fun — and the colors were brilliant! We Wonder if you have a favorite type of fish, or if you have fish of your very own? Thanks for WONDERing with us today! :)

  6. This was a great WONDER. My science class has its own coral tank.

    I think tomorrow’s WONDER is going to be about how the brain works, thinking, or something that needs lots of brain power.

    • Hi there, Wonder Friend Angelina! WOW, it’s pretty cool that you can check out a coral reef tank in your science classroom– lucky duck! :)

      We Wonder what your aquarium would look like if you could design it on your own?

      Thanks for commenting today and sharing your cool guesses for tomorrow’s Wonder of the Day®! We think you’re onto something…! :)

    • Way to go, Kristi! We are really excited that today’s Wonder made you smile! It’s so fun to learn something new at Wonderopolis– now you are even closer to becoming a fish expert! Way to go! :-)

  7. We thought that today’s wonder smelled very fishy. The Angel fish was heavenly.

    We think tomorrow’s wonder will be about how your brain wonders, dreaming, how a wonder is created, thinking, or BRAIN teasers.

    We are wondering who decides what the Wonder of the Day will be? Who does the research? Who types the wonders? Are there a lot of people working on this web site? Or are you a robot. (Kaden really is the only one wondering that.) Do lots of people answer the comments or is the Wonder Comment Person one person or a robot (Kaden, again.). We are sure enjoying this daily brain warm up! Thanks for helping us wonder…robot or not. :)

    • You were oh-so-right about today’s fishy Wonder, Mrs. Ski’s PM Class! ;)

      We are so excited that you enjoyed today’s Wonder… it sounds like the Angel fish is a favorite among many! We have lots of Wonder Friends who work on our Wonders of the Day®! Everyone must work as a team, but be responsible for different parts of the Wonder process. Our Wonder Friends develop the Wonder (with the help of your suggestions!), find cool images and videos to use, and make sure Wonderopolis.org is working perfectly!

      Our Wonder Friends take turns answering your AWESOME comments– it’s fun to communicate through the Internet with our friends around the world! We are so excited that you are WONDERing with us today– we hope you have a SUPER rest of the day! :)

    • Thanks for WONDERing with us today, Gina M! We like your un-Halloween greeting! We hope you had lots of fun trick-or-treating! :)

  8. Thanks for today’s Wonder. Over half our class has a fish tank at home. We also have a fish tank in our classroom. Will thinks the fish were beautiful.
    We think tomorrow’s Wonder might be about how our brain works and wonders. We are really wondering about tomorrow’s Wonder…

    • WOW, Mrs. Thomas’ Tigers, you’ve got LOTS of fish experts in your classroom!! We also enjoyed today’s Wonder… the colors of the fish in the aquarium are beautiful! We look forward to WONDERing with you tomorrow! :)

    • Well thanks, Wonder Friend Phoenix! It sounds like you’re an animal lover– we like your style! We hope you will come back tomorrow to see what the next Wonder of the Day® will be! :)

    • What a great Wonder, Bianca! We bet that certain fish enjoy colder temperatures if their original habitats are closer to the ocean floor. Others, like tuna, swim very close to the top of the surface, so the temperature of the water is warmer. However, we bet you could do some WONDERing of your own to find out more information. We’d love to see what your research shows! :)

    • HOORAY, we’re so happy you liked our Wonder today, Bianca! Did you have a favorite piece of information that you learned? :)

    • We Wonder if you have a favorite color or a favorite fish, Elizabeth? We are so glad you enjoyed today’s Wonder… the fish in the aquarium are very lovely to watch! We hope you have a WONDERful day! :)

    • Hi there, Wonder Friend Bianca! While we certainly don’t know everything, we really enjoy learning, using our imaginations, and finding great information to share with our Wonder Friends! We Wonder if you have a favorite thing to think, daydream or Wonder about?! :)

    • We Wonder what it is, Bianca? You don’t have to share if you don’t want to, but we really enjoy WONDERing about birds, dance, music, animals and their homes, electricity, space… the list goes on and on! That’s why we have so much fun with all our Wonder Friends! We learn something new every day! :)

    • We really love to dance at Wonderopolis, Bianca! Thanks for sharing with us– we are so glad you are here today! We’ll see you soon, Wonder Friend! :)

  9. Thanks for discussing about Saltwater Fish. I appreciate your work and this blog post. Great work, keep this carry on. I would like to visit again and like to read some more interesting information. :)

    • We are so excited for you, Madi! What a fun pet to have – a fish! WOHOO!

      You would be able to taste the difference between saltwater and regular water – your tastebuds will do all the work. :)

    • Hi Gabby! Thanks for WONDERing with us! The fish come from all over the world where they’re native! Have you ever been to an aquarium? Keep WONDERing! :)

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Have you ever wondered…

  • Do fish in aquariums swim in freshwater or saltwater?
  • What are some popular fish that can be raised in aquariums?
  • How do you maintain an aquarium?

Wonder Gallery

760 aquarium shutterstock_114904582Vimeo Video

Try It Out

Ready for a field trip? If you love fish and would like to learn more about what it takes to raise fish in your very own aquarium, ask the experts!

Grab a friend or family member and take a trip to your nearest pet store or exotic fish store. Check out the varieties of fish they sell. Do they have both freshwater and saltwater fish?

What kinds of aquariums do they sell? What’s the largest aquarium they have at the store? If you were to get an aquarium, what type would you want? What types of fish would you want to raise?

Raising fish in an aquarium can be a daunting task. Do you think you’re up for the challenge? Be sure to discuss things with your family before taking on the responsibility of an aquarium. Ask the experts at the store what you’ll need to do to maintain your tank, so you’ll have a clear picture of what’s in store for you as an aquarium and fish owner.

If you already have an aquarium, we’d love to hear about your fish and see pictures of them! You can share your aquarium and its inhabitants with your Wonder Friends by posting pictures on Facebook. We can’t wait to see your aquatic friends!

Still Wondering

In National Geographic Xpeditions’ Aquarium Habitats lesson, children consider how aquariums can provide realistic habitats for marine animals. They use the Internet to visit three aquarium habitats and determine whether these aquariums succeed in providing high-quality environments for the animals that live in them. They conclude by designing their own aquarium habitats based on what they have learned.

Wonder What’s Next?

If you WONDER about tomorrow’s WONDER, then you’ll love tomorrow’s WONDER!

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