How many corys in a 20 gallon?

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pettygil

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How many Corydoras, can I put in a 20 gallon tank, along with 9 glow Tetra fish? :fish1::fish2:
 
Cory cat fish

20 gallon high or 20 gallon long?
And what kind of Cory are you talking about?

I'm not sure, but I think it's a cory cat fish. He likes to hang out at the bottom of the tank, thoe, sometimes like to swim. Once the tank cycles.. I am going to add him to my 20 gallon. I named him Cory. I know an original name. :lol:
I'm not sure if he, is an He, or a she. Here is a video of my Cory cat fish.

 
Your Cory doesn't look well to me...I suspect ammonia or nitrite was too much for it.

I'd use some Seachem prime and do a partial water change. The prime will detox what's in your water.

In the future, I would try a fishless cycle.
 
Cory looks fine to me, he also is swimming, he also eats.

Your Cory doesn't look well to me...I suspect ammonia or nitrite was too much for it.

I'd use some Seachem prime and do a partial water change. The prime will detox what's in your water.

In the future, I would try a fishless cycle.

Cory looks fine to me, he also is swimming, he also eats. That is a good sign of a healthy fish, if they eat. He was resting on a leaf, but if you watch the rest of the video, Cory is swimming. What I'm saying why do think he is un healthy?
My N02 is 3, after water change.
Ammonia is 0.25
 
I attached a clip of my cories to check out. Usually cories like to be busy snuffling around the substrate. That's typical Cory behavior.

I am thinking that the ammonia and nitrites were too much... I'd do a water change and add prime to detox the ammonia and nitrites.

Here's my cories.
https://youtu.be/4B41igzzrJw
 
You have beautiful fish.

I attached a clip of my cories to check out. Usually cories like to be busy snuffling around the substrate. That's typical Cory behavior.

I am thinking that the ammonia and nitrites were too much...


Here's my cories.
https://youtu.be/4B41igzzrJw

You have beautiful fish. I am doing Water Changes everyday, and adding, water conditioner. And I'm adding API Quick Start to help get my tank to cycle. I do not know what else to do. I am not sure if my test strips are accurate. I'm going to have to buy API master test kit.
 
I put my cory fish in a 20 gallon tank, cause he was not doing too well in the 6.5 gallon, uncycled tank. I thought he was dead, but he is not dead. Once my 6.5 gallon tank cycles I will add my betta fish. The other 6.5 tank is closed to being cycled.
 
How many Corydoras, can I put in a 20 gallon tank, along with 9 glow Tetra fish? :fish1::fish2:
I would try and keep a group of 6 corys. Try and get them all the same species. Can you post a clear, in focus, profile photo so it can be identified. Your videos arent very clear.
 
Image of my fish

Pic of my Cory Fish.
thumbnail.jpg
 
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You have beautiful fish. I am doing Water Changes everyday, and adding, water conditioner. And I'm adding API Quick Start to help get my tank to cycle. I do not know what else to do. I am not sure if my test strips are accurate. I'm going to have to buy API master test kit.

Thank you ? good luck to you! Aiken and Andy are knowledgeable.
Seachem Prime is a good conditioner, add that to your shopping list, too.

I probably won't be on here as much because my tank is doing well ?. I tend to show up on here when I have a problem or I am in the mood to learn from the wise sages that came before....lol
 

That appears to be a Peppered Cory and if so, you can ( and should) keep a school of about 6-8 of these if you have a 20 long or a school of 4-6 if a 20 high. Bottom line, cory cats do better in schools rather than alone. Be aware that Peppered Cories should get to about 3" so they will take up a lot of your tanks' fish bioload.
 
Tanks for the reply.

That appears to be a Peppered Cory and if so, you can ( and should) keep a school of about 6-8 of these if you have a 20 long or a school of 4-6 if a 20 high. Bottom line, cory cats do better in schools rather than alone. Be aware that Peppered Cories should get to about 3" so they will take up a lot of your tanks' fish bioload.

I did not see this post, until now. So I can buy 5 cory's for my tank, I like Cory's they are a neat pet. Sometimes he swims, other times he, or she is in the gravel. I love my Cory, he is soo cool. I have a 20 high.
 
I did not see this post, until now. So I can buy 5 cory's for my tank, I like Cory's they are a neat pet. Sometimes he swims, other times he, or she is in the gravel. I love my Cory, he is soo cool. I have a 20 high.
If they are smalls ( 1" or less size) , you should be able to get away with adding 5 more but as I said, these fish get large enough that you really shouldn't add much more for a while until your tank gets more established. If they are mediums ( 1 1/4" + size) , I wouldn't add more than 3 more. When your tank is more mature, you can add more. (y)
 
About how many corys or any sort of fish in a given tank.........
I doubt that any fish can count. So, if you have at least three of a given species, I suspect the fish will feel at home . In fact, your home that you give them is most likely the best they ever had.

Those numbers are just what someone guessed at one time and is not written in stone
So, let's not get hung up on often meaningless numbers. :)

There are some variables of course. How is you water change routine? How dirty are the fish you have, etc......
 
About how many corys or any sort of fish in a given tank.........
I doubt that any fish can count. So, if you have at least three of a given species, I suspect the fish will feel at home . In fact, your home that you give them is most likely the best they ever had.

Those numbers are just what someone guessed at one time and is not written in stone
So, let's not get hung up on often meaningless numbers. :)

There are some variables of course. How is you water change routine? How dirty are the fish you have, etc......
While you make an interesting argument, some numbers are not arbitrary or meaningless. It has to do with natural habits, personalities of species, reproductive successes or failures, etc. With cory cats, the more the better. The problem is that a nice sized school needs a large tank and the OP has a small one. Most cory species do not do well alone. Pairs are iffy depending on the size of the tank. 3 will tend to spark the natural schooling desire in the fish. If the 3 are all the same gender, that can pose a problem. In the case of livebearers, males are so used to breeding that they can literally screw the female to death should there only be one so you add more females to hopefully keep him from overdoing a single female. In the wild, a male Guppy would be among 30-50 females so no need to worry about overdoing any one female.
If I understand the OP, she WANTS a school of cories so needs to know how many will fit in her tank.
 
I do a 50% water change weekly

About how many corys or any sort of fish in a given tank.........
I doubt that any fish can count. So, if you have at least three of a given species, I suspect the fish will feel at home . In fact, your home that you give them is most likely the best they ever had.

Those numbers are just what someone guessed at one time and is not written in stone
So, let's not get hung up on often meaningless numbers. :)

There are some variables of course. How is you water change routine? How dirty are the fish you have, etc......

I do a 50% water change weekly. I have 9 glow tetra's and 3 red eye tetras in the 20 gallon tank, and two Endless, live bearer's in a 6.5 gallon tank. I am going to buy 4 cory fish. Then after a few months, buy a couple more. I also am going to buy a few Betta's i am not sure where to buy my Betta's, as of yet. If anyone can direct me to a place where they sell Betta's online, feel free to direct me with a link and I'll go check it out.
 
I think 5 Cory fish would be ok in a 20 gallon tank.

While you make an interesting argument, some numbers are not arbitrary or meaningless. It has to do with natural habits, personalities of species, reproductive successes or failures, etc. With cory cats, the more the better. The problem is that a nice sized school needs a large tank and the OP has a small one. Most cory species do not do well alone. Pairs are iffy depending on the size of the tank. 3 will tend to spark the natural schooling desire in the fish. If the 3 are all the same gender, that can pose a problem. In the case of livebearers, males are so used to breeding that they can literally screw the female to death should there only be one so you add more females to hopefully keep him from overdoing a single female. In the wild, a male Guppy would be among 30-50 females so no need to worry about overdoing any one female.
If I understand the OP, she WANTS a school of cories so needs to know how many will fit in her tank.

I think 5 Cory fish would be ok in a 20 gallon tank, or 4, not sure. And I do not know if they are male, or female. Do Corys breed, or eat their babies? like guppies do.
 
I feel dumb asking this question

FWIW... I did say say "at least three" :)

I feel dumb asking this question but do you mean 3, or more cory's. Or do you mean 3 and no more cory's? Did this confuse you. I think you meant buying 3 and no more fish. Somehow I ended up over crowding my post with all this fishes. Look! I did it again. lol.
:ROFLMAO::fish2::fish1::fish1::fish2:::fish2::fish1::fish2::fish1::fish1::fish2:
 
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