Ideal fish for small tanks?

[ClownLurch]

Why do Medaka "need a group", they are commonly kept in pairs in Japan when breeding for specific traits.

I believe they live in groups in the wild. Would you be willing to compromise with “prefer” rather than “need”?
Living in pairs seems to be a situation created by mankind as you yourself point out.

 

[Dees Creatures]

I don't suggest betas bc there solitary so you would only be able to get one beta nothing else.
3 tetra's and two dwarf frogs bc I got a 5-gallon that is just a bit smaller than yours and I have 3 tetra's and two dwarf frogs there freshwater but I have to feed my frogs by hand or else they won't eat since dwarf frogs are nocturnal dwarf frogs eat pellets blood worms and other's tetras eat fish flakes and blood worms so you might be able to get away with just blood worms but my tetra's like the flakes the best and one of my frogs almost starved to death bc he wouldn't eat the pellets bc he didn't like them bc later I picked him up but kept him in the water I put the pellets in front of him he didn't eat them then I took blood worms in front of him and he went to town on them. My other dwarf frog eats whatever pellets or bloodworms.

 

[OliveFish05]

I don't suggest betas bc there solitary so you would only be able to get one beta nothing else.
3 tetra's and two dwarf frogs bc I got a 5-gallon that is just a bit smaller than yours and I have 3 tetra's and two dwarf frogs there freshwater but I have to feed my frogs by hand or else they won't eat since dwarf frogs are nocturnal dwarf frogs eat pellets blood worms and other's tetras eat fish flakes and blood worms so you might be able to get away with just blood worms but my tetra's like the flakes the best and one of my frogs almost starved to death bc he wouldn't eat the pellets bc he didn't like them bc later I picked him up but kept him in the water I put the pellets in front of him he didn't eat them then I took blood worms in front of him and he went to town on them. My other dwarf frog eats whatever pellets or bloodworms.

There are many types of tetras, and the majority would never fit in a five gallon. Tetras are schooling fish, which means they need to be in groups of 5 or more, with 8 being an ideal minimum number. Five gallons does not provide the swimming space to meet the needs of most tetras, much less allow enough space for the numbers needed. Tetras would not be a good choice for a 5 gallon or 25 liter tank. I don’t know much about frogs but I know they have very specific diets. Because if this, it is best not to keep them with fish. Because of the size of the OPs tank, a solitary fish like a betta WOULD be ideal.

 

[Dees Creatures]

There are many types of tetras, and the majority would never fit in a five gallon. Tetras are schooling fish, which means they need to be in groups of 5 or more, with 8 being an ideal minimum number. Five gallons does not provide the swimming space to meet the needs of most tetras, much less allow enough space for the numbers needed. Tetras would not be a good choice for a 5 gallon or 25 liter tank. I don’t know much about frogs but I know they have very specific diets. Because if this, it is best not to keep them with fish. Because of the size of the OPs tank, a solitary fish like a betta WOULD be ideal.

i have three tetras and they are happy I have noticed that they even made a game sometimes there play a game where they have to try so wimm under the filter as fast as they can. my teras are happy and show no sign of depression

 

[Byron]

i have three tetras and they are happy I have noticed that they even made a game sometimes there play a game where they have to try so wimm under the filter as fast as they can. my teras are happy and show no sign of depression

I'm going to offer some data here that I hope will help you to understand what @OliveFish05 is referring to when she said they need a group. And first before that, welcome to TFF.

All tetras are what we term shoaling (sometimes schooling) fish. They live in groups numbering usually hundreds. Many other types of fish we keep in aquaria are the same--rasboras, danios, barbs, loaches, cory catfish, rainbowfishes, and probably some I can't remember. What must be understood is that this "expectation" of living in a group is part of the genetic make-up of the individual species. The individual fish within such a species will be stressed without the security a largish group provides. Some species have other issues connected with group, but one common to all such fish is the security the group provides.

Obviously we cannot usually if ever provide a group of hundreds of the species, but we can ensure there are enough of them to avoid significant stress. Stress is the reason for 90% of the diseases aquarium fish contract; in other words, if we avoid stress, we are avoiding 90% of possible disease issues. Ich or white spot for instance is only going to occur if the fish are seriously stressed; even if the parasite is present, non-stressed fish will in the majority of cases be able to manage and not become infected. So these factors, like numbers, become a very important aspect of maintaining healthy fish.

It is impossible for any of us, no matter who, to really be certain that the fish in our tank is healthy or "happy," if that is something fish feel [I'm of two minds on this "happy"], unless we ensure we have provided the best environment for the fish. And a major factor in this concerns the numbers.

A study in 2009 (going from memory) looked into this specific issue--how the number of fish of a shoaling species in an aquarium might affect the fish. The results were interesting and very clear. The lower the number of fish of the species, the more aggressive the individual fish tended to become. The species were kept in groups of three, five and ten (in separate tanks obviously), and without exception the least stressed, more peaceful, and healthier fish were those in the groups of ten. Aside from aggression, the study found that the number in the group had a direct impact on the fish's shoaling behaviour, upon "darting" from various things, and even a greater latency to feed. The fish were without any question in considerably better condition the more of them there were in the tank.

I don't know the species of tetra here, but a 5g tank is too small for all of them, with the possible exception of the Ember Tetra, but I would consider even for this nano species a 10g tank minimum.

Don't hesitate to ask any questions on this, I would be glad to explain anything that is not clear.

 

[itiwhetu]

As long as your water parameters are correct. Fish like Mosquito Rasboras or Clown Killifish would be fine in your tank

 

[Essjay]

There is more information in post #11 in the competition thread

Vote Now - December 2021 Fish of the Month Contest (any fish)

POLL HAS ENDED Fish of the Month :big_boss: PLEASE VOTE! We have 8 awesome fish entered into December's 2021 Fish of the Month Contest. View all the entries and descriptions below and then go to the top of page - click on your choice for FOTM and then click the "cast" button. Please DO NOT...

www.fishforums.net

 

[TwoTankAmin]

I keep a group of cwlestial pearl danio (Celestichthys margaritatus) and some cherry red shrimp in a planted unheated 5.5 gal tank (it is on a shelf about 6 ft. up a wall).
https://www.seriouslyfish.com/species/celestichthys-margaritatus/

 

[woyzeck]

I worry over situations
I know will be alright
Perhaps it's just imagination
Day after day it reappears
Night after night my heartbeat shows the fear
Ghosts appear and fade away

 

[OliveFish05]

I'm going to offer some data here that I hope will help you to understand what @OliveFish05 is referring to when she said they need a group. And first before that, welcome to TFF.

All tetras are what we term shoaling (sometimes schooling) fish. They live in groups numbering usually hundreds. Many other types of fish we keep in aquaria are the same--rasboras, danios, barbs, loaches, cory catfish, rainbowfishes, and probably some I can't remember. What must be understood is that this "expectation" of living in a group is part of the genetic make-up of the individual species. The individual fish within such a species will be stressed without the security a largish group provides. Some species have other issues connected with group, but one common to all such fish is the security the group provides.

Obviously we cannot usually if ever provide a group of hundreds of the species, but we can ensure there are enough of them to avoid significant stress. Stress is the reason for 90% of the diseases aquarium fish contract; in other words, if we avoid stress, we are avoiding 90% of possible disease issues. Ich or white spot for instance is only going to occur if the fish are seriously stressed; even if the parasite is present, non-stressed fish will in the majority of cases be able to manage and not become infected. So these factors, like numbers, become a very important aspect of maintaining healthy fish.

It is impossible for any of us, no matter who, to really be certain that the fish in our tank is healthy or "happy," if that is something fish feel [I'm of two minds on this "happy"], unless we ensure we have provided the best environment for the fish. And a major factor in this concerns the numbers.

A study in 2009 (going from memory) looked into this specific issue--how the number of fish of a shoaling species in an aquarium might affect the fish. The results were interesting and very clear. The lower the number of fish of the species, the more aggressive the individual fish tended to become. The species were kept in groups of three, five and ten (in separate tanks obviously), and without exception the least stressed, more peaceful, and healthier fish were those in the groups of ten. Aside from aggression, the study found that the number in the group had a direct impact on the fish's shoaling behaviour, upon "darting" from various things, and even a greater latency to feed. The fish were without any question in considerably better condition the more of them there were in the tank.

I don't know the species of tetra here, but a 5g tank is too small for all of them, with the possible exception of the Ember Tetra, but I would consider even for this nano species a 10g tank minimum.

Don't hesitate to ask any questions on this, I would be glad to explain anything that is not clear.

Brilliant explanation, as always!