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What is your favorite brand of goldfish food?

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What is your favorite type of goldfish?

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Comet Goldfish

comet goldfish

Quick Statistics for the comet goldfish
Temperament: Community
Family: Cyprinidae
Native To: Asia
Diet: Omnivore: can be fed pellets and flakes
Adult Size: larger than 12"
Temperature: 65° - 78°F
Care Level: Relatively Easy
Scientific Name: Carassius auratus
Environment: Freshwater

The comet goldfish variety is thought to have originated from the United States around the 1800s. It is a single-tail long bodied goldfish and is most often what people think of when they hear the word goldfish. This goldfish variety is an excellent choice for beginners. It is a hardy strain that can be kept in an outdoor pond or aquarium. 

The comet looks a lot like the common goldfish in appearance, except that its fins are longer and sleeker. The caudal fin on the comet is almost as long as the its body in a good specimen, but it can still be held erect. The caudal fin is deeply forked, and the lobes are sharply pointed. A large specimen with a twelve-plus inch body and tail of greater or equal length makes for an impressive sight. In the best specimens, the tips of the tail are almost clear, which produces a beautiful effect against the background color of the fish and fins. Comets come in a variety of colors including silver and yellow, as well as a combination of these colors. While they are often metallic in color, nacreous comets are not all uncommon. Much like the common goldfish, comet goldfish are fast and agile swimmers. Comets are smaller than the common goldfish and only grow to a length of about 6 to 10 inches in an aquarium, but they can reach a length exceeding 12 inches in a large pond.

Comets are prolific breeders and are bred commercially for sale to pet shops throughout the United States and elsewhere in the world. The most popular comet variety is known as the Sarasa, which can be recognized by the white patterning and deep red extending over the fins and body. Comets will often thrive in outdoor ponds but can be susceptible to fin congestions during long periods of cold weather.

comet goldfish


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There are 29 comments
Posted by Callie – London

I have 2 comets, a shubunkin, and a common. They are all 6 inches and live in a 100 gallon tank. Could I get some more fish?

Posted by Jeannie – Tennesee

I have been reading some of the posts on here and there seems to be a lot of questions. I have had goldfish for about 20 years now. I currently have 6 beautiful goldies of different breeds in my 75 gallon tank. Here's the basics. Goldfish are heavy poop producers, which is full of nasty toxins. To keep your tank clean buy the biggest filter you can. I have 2 HOB, (hang on back) filters that are rated for 75 gallons, that way I have double the output. Fish bowls are bad, get a tank. The bigger the tank the better. You need at least 10 gallons per fish. Don't over populated your tank. I know it's tempting, but don't. A crowded tank is harder to keep clean.
Air is a must. Buy a air pump and a air stone of some kind. Your fish will be more active if they have plenty of oxygen in the water. I have 2 9" airstones in my tank. The fish love swimming through the bubbles! Goldies can live in cold water, but they are more active in water around 68-70 F. Room temp. basically. I have a thermometer that sticks on the outside of the glass ( it's like a sticker), my goldies think the in the tank thermometer is a toy and they break them!
When you add water to the tank make sure it is cool, not warm. Warm water is bad, if they get too warm they will try to jump out of the tank. So watch your temp when using a heater in winter!
Feeding. Goldfish have no stomach. So of course they are hungry all the time. Overfeeding them can cause heaps of issues. I feed mine twice a day, sometimes 3 times if they really are begging. Goldfish will eat pretty much anything as long as It's vegetation, like lettuce, fruit, ect. Flakes and pellets are fine, and mine love freeze dried blood worms, algea tabs. I don't give them more than they can consume in 2 minutes. Trust me a lot will land on the bottom and they will get it later when they picking up the gravel.
Salt. Salt is great for all tanks. Aquairium salt that is. Not table salt. It helps good bacteria grow and kill off bad, and it will keep your fish healthy! It's a must even for freshwater tanks. A little will not hurt your fish.
Cleaning is a major thing when your talking about a tank. In my case stripping the whole tank is a major undertaking, and I only do it when I am totally redoing everything. Tank up keep is easy. If you have a HOB change your filter once a month and do a 20% water change, and vacuum your gravel. I have a gravel vacuum that extracts water also, so it's me doing 2 chores in one step. You can buy them at any pet shop or online fairly cheaply. When you add fresh water to the tank make sure It's cool to the touch and be sure to treat it before adding it to your tank. If you do this once a month your fish will be healthy and your tank will stay clean!!

Posted by Kim/Nicholas – Flatrock,NL

Our son has had several comets and today the last on Scooby Doo 2nd died:( He was about 1 yr old,his other fish friends kept dying ad he was our only one left:( We noticed that he hasn't been very active lately and the last couple of days there has been a clear,slimy,gel like substance in the tank.We were wondering what that substance is??? Our water has been tested several times and it was fine,we even use Nutrafin Aquaplus when we change the water.Hopefully you can help us!
Can you also give us a couple of types of goldfish that
live longer???
Thanks for your help.

Posted by Narakai – Australia

My first fish was a tiny lemon comet just after christmas - I have had him now for a little over 4 months and he is growing so quickly. He is absolutely stunning. He shares his tank with a small blue oranda, a young red comet and the newest arrival a young chocolate oranda. They all delight me so much and look wonderful together. I have a 100 litre tank and they are all just booming along. L love my new hobby.

Posted by ErnieMac – Colombia

I'm kind of new at this!...

I have a two inch long red cap oranda (emilio), a one inch black moor goldfish (martin), and an inch and a half long comet goldfish (hugo), all in a 24liter tank. The red cap always eats his pal's food, how can I feed them (tetrafish goldfish crisps) without having to separate them? How many times a day and how many flakes should I feed to each fish? Is the size of the tank going to affect their normal growth? What temperature is ideal for them? Also, they told me at the store that the size of the tank is fine for all three, but in some of your comments, I can see that each fish needs at least 10 gallons??? :O

Reply to ErnieMac
Posted by K.Jackson – Bakersfield

Hi Ernie,
I can relate to your situation. I got into the hobby about a year ago. I found that often, pet store employees are not very knowledgeable. I started out with 6 comet goldfish and was told that they would be fine in a 30 gallon tank but the truth is they will grow way too large to be permanently housed in such a small tank. Within 5 month they doubled in size!

Needless to say 6 gallons is WAY to small for even one fish when you consider that a fully grown, healthy comet can get 12 inches long. It will stunt their growth, it will not be enough water to maintain good water quality and they will be susceptible to disease.

Honestly, goldfish as adults should be in a pond although the most popular thing is to leave them in a tank, stunt their growth, stress them out, and have them die early (Goldfish can live for decades). Also, its not about the volume its about the surface area. I have 2 comets in a 4ft by 2ft above ground circular pond on my patio. Its only around a 100 gallons but its 8cubic feet. Given that they are mainly lateral swimmers, that is plenty of space for now .(A larger surface area is also great for aeration.) I have noticed that they have been growing faster than they ever did in their old tank. I recommend you buy the largest tank possible, period. If you are low on cash I can tell you about some creative non-glass alternatives (not as ascetically pleasing).

OK. thing two, Goldfish can be housed with others types but its best to get ones that are similar in size and body conformation. The oranda is the largest and might decide to chase the others during feeding. You can feed them anywhere from three times a day to once every two days depending on you set up and water quality. Generally you only want to feed enough for them to eat all the food off the surface within a few minutes. If you overfeed this will lead to bad water quality and fat fish. Is you tank cycled? I would recommend feeding very sparsely until you get a larger tank.

68-75degrees is optimal.

However, you will notice as the comet (long sleek body and wedge shaped head) gets larger he will swim much faster than the others (telescope eyeballs, large head cap, and short rotund bodies) and out compete them for food. This will may also become a concern because if the comet starts chasing the moor or oranda they will become tired and stressed. I hope this helps.

Reply to ErnieMac
Posted by fantailer

Yes you neeed a 30 gallon tank for 3 goldfish.

Posted by Amanda

Yesterday I bought 2 comet goldfish. Buttercup and Wesley (from princess bride :)) Buttercup seems to be doing fine but Wesley seems to just be hanging out at the bottom of the tank not doing much. What do you think is wrong? Or is that normal? The water seems kinda cold but Im not sure how cold because I dont have thermometer. Any tips?

Reply to Amanda
Posted by matt – snowy north

easy buy a thermometer. they sell ones with suction cups that you can stick to the inside of your tank. but if the water has sat for more than a day its most likely close to room temp which is what most goldies like, i live in a frostbelt state so i keep a close eye on where my tank is in my house and always keep an eye on the temp.

Posted by lisai

Comets are my favorite type of goldfish. I have 3 sarasa comets (Dian, Tou, Wei) and 1 orange comet (Tora).

Posted by abiel – Houston tx

I've had two common goldfish for 10 yrs and added a white commet and they get along great and my commet really added a sparkle to my aquarium.

Posted by Leah – Australia

@ Izzy
Your tank already has too many fish in it. Goldfish need at least 40 liters (10 gallons) per fish. They will be okay in that small tank for a few months but will definitely need a bigger tank in the future. Otherwise their growth will become stunted and the water quality will be poor and poison the fish. Make sure your tank also has a filter to remove their waste from the water :)

Reply to Leah
Posted by ErnieMac – Colombia

Hello Izzy, I have had a small (inch and a half long) comet goldfish for about four months. It was given to me on my birthday on a fish bowl and was told repeatedly that it was not the appropriate place for a fish to live in. So now he's in my brand new fish tank with two more pals! the fishes are relatively small. I have a redcap Oranda that measures about two inches long, and a black moor that measures about one inch long. The tank holds about 22.08 liters (5.83 gallons). Is that really too small for these fishes lo live in??

Thank you.

Reply to Leah
Posted by fantailer

ErnieMac for your goldfish to grow happy and healthy you need a 30 gallon tank at the minimum

Posted by Izzy – .....

I recently got 4 new comets and now is completely hooked on fish-keeping. I have a ,maybe, 28/30 litre tank, how many comets or other goldfish can I keep in there together. If I add a couple of veiltales will they be okay together?

Posted by Dexter

I got a 4 1/2 year old comet goldfish today from my sister and it's fantastic. It's tailfin is long as its body and it already recognizes me. So far I have taken great care of it, cleaning its tank and feedingnit the right ammounts of food. It's just wonderful having it :-)

Posted by AMY – australia

i have 5 commets,1 blackmoore,2 catfish(sucker ones)and 3 of my commets looks exactly like number six it is huge!!my sister gave it to me because it outgrew her small tank and i have a big-ish tank she had it r about 3 years and it was tiny when she got it and now it sooo big and its really strong (like when i scooped him up in little net he felt soo strong) fish r gr8 pets:) so relaxing

Posted by jimmy – Australia

I have gorgeous 2 goldfish. A common and a Sarassa Comet. Ever since i bought my beautiful comet I have searched everywhere for an explanation as to why she has a a row of extremely large scales on each side centred on her lateral line. There is a few larger but much smaller scales just before her dorsal . She is in good health and totally normal in every way.
If you picture a Doitsu koi this is exactly what the scales look like. She is definately a goldfish, not a koi. She did spawn with my male once before but i have absolutely no space to raise any fry, but would have loved to and i often wonder if their fry would have large scales too.
Is this a deformity? Why does she look like this?

Posted by paige

I have a beautiful comet named Oscar which I won from a carnival and he's now 3 and he's great! I love him soo much :)

Posted by Jessie – Florida

I was at my school Spring Fling yesterday. There was a game where you could win a goldfish by throwing a ping pong ball into a fish tank thirty feet away. I got the ball into the tank and won a white comet goldfish. He was so untaken care of. They dumped him into a plastic bag and poured tons of water on him. I took him straight home and put him in my giant filtered tank. At school he looked sick, but now he is swimming all around the tank very happy. I named him BillyBob. I think I saved his life!

-Jessie & BillyBob

Posted by Crystal – IL

I have a common goldfish and was wondering if I could add a Shubunkin, Comet, Fantail, Veiltail, and Ryunkin Goldfish. Is this a bad mix?

Posted by Steven – Connecticut

In response to Alex in California:

Your fish sounds like they have fin rot. This is when the fish's fins become to become "easten" and soon become torn and so forth. There are medications to treat this, which I would look into, but before you treat your fish, first identify if it is fin rot.

Posted by Alex – California

I bought my comet fish less than a month ago. He's bright orange and beautiful. When i first got him his tail was long and flowing and sleek. All of a sudden his tail looks ripped, as if a majority of it has been "bitten off". What is this? Is he sick? Is there anything I can do for it?

Posted by CHRIS


Posted by Tia – Somewhere..

You are only suppose to house 2 in a 50 gallon at a min. I have 3 in a 300+ gallon pond.

The white ones are so beautiful.

Posted by jodie – scotland

my comet is too big for my tank what tank size do i need?

Posted by adanoon – ohio

my comet looks just like#7

Posted by Katarine

AWWW My fish is a comet.. I think. He looks like these guys only he's white with a red saddle on his head. I think those breeds are called Tancho single tail Comets? Anyway, he's just as cute as these guys, but will he really live for a long time?

Posted by GYTASSSSSSS – Ireland

thid fish looks very very nice to me