Betta killed cardinal

[ChloChlox]

Hi everyone,
Sorry to bother you. My female Betta just killed my cardinal tetra and now she’s ill. I introduced 4 cardinal tetras into her 10 gallon tank thinking it would be okay, my LFS said it would be fine, but within an hour or so of putting them in the tank she attacked one of them. She's quickly gone downhill from here, she is floating to the top and resting at the surface on her side, she is also struggling to swim. I would usually only research these symptoms alone, but its the facts it happened so shortly after her killing it that's worrying me.
Thank you and hopefully someone can help

 

[Retired Viking]

Sorry about your fish. Did you check her for injuries? I would return the surviving cardinals to the LFS. 10 gallon tank is too small for cardinals and they need to be in shoals of at least 6 or more.

 

[ChloChlox]

Sorry about your fish. Did you check her for injuries? I would return the surviving cardinals to the LFS. 10 gallon tank is too small for cardinals and they need to be in shoals of at least 6 or more.

I think she might have a small injury on her side? I’m not sure though, will definitely return the cardinals. I’m so sorry I didn’t do enough research on them, I haven’t had fish too long so I took the fish shops word for it. Thank you so much for the reply.

 

[Retired Viking]

I think she might have a small injury on her side? I’m not sure though, will definitely return the cardinals. I’m so sorry I didn’t do enough research on them, I haven’t had fish too long so I took the fish shops word for it. Thank you so much for the reply.

Never believe workers at the LFS most do not know or do not care unfortunately. Most tetras need lots of room and at least 6 fish to be healthy long term. I keep my tetra in a 55 gallon tank. 10 gallon is good for a single male betta or a couple of female bettas. Also shrimp and snails do well in that size tank. Other members may have additional recommendations as far as fish for a 10 gallon. My smallest tank in use is a 20 gallon long. I have several empty 10 gallon tanks I may use for furture fish breeding.

 

[Lajos_Detari]

Both male and female Bettas are aggressive fish. They are called fighting fish in my country and they have the fighting and killing instinct.

They can only be kept with bigger fish and provided the big fish don't nip their fins (if they have big fins).

Its difficult to know the problem unless we know all the symptoms snd see its condition.
Can you take a photo of your Betta?

 

[ChloChlox]

Both male and female Bettas are aggressive fish. They are called fighting fish in my country and they have the fighting and killing instinct.

They can only be kept with bigger fish and provided the big fish don't nip their fins (if they have big fins).

Its difficult to know the problem unless we know all the symptoms snd see its condition.
Can you take a photo of your Betta?

Hi sorry only just seen this, it was a bit difficult to take a picture so I hope this is okay. She seems to be doing a little better, but I will an eye on her later, it’s 5 am so I’m not sure. If it’s not a good photo I could provide another one later if that’s okay. I know the water level looks like it’s gone down a bit, that’s just because I took some of the water to acclimate the tetras to a different tank so that they can be safe before I return them. I will top it up later. Thank you so much for replying.

 

[Lajos_Detari]

How was the Betta condition when you saw it in the fish shop?
Was it lethargic or not really moving much?
Also, how was the Betta being kept in the fish store?
Was the container very small and what is the colour of the water in the tank?
Was the tank water very yellowish and dirty?

Most Bettas were kept in very poor condition in the fish stores.
So, by the time you brought it home, it's almost half dead.
It might also be infected with disease if they feed it with tubifex worms.

Anyway, firstly, do a large water change of more than 50%.
Make sure the temperature of the tank is warm at around 27degC.
Betta doesn't like cold water.
Monitor its condition.
Look for any symptoms of disease such as fast breathing, lethargic, any white spot on the body/fins, skin peeling off, any abnormal growth on the body, clamp fins, etc.

Note: You may have to use salt later if it's really sick. (about 4 tablespoon of salt for 10 gallons).

 

[ChloChlox]

How was the Betta condition when you saw it in the fish shop?
Was it lethargic or not really moving much?
Also, how was the Betta being kept in the fish store?
Was the container very small and what is the colour of the water in the tank?
Was the tank water very yellowish and dirty?

Most Bettas were kept in very poor condition in the fish stores.
So, by the time you brought it home, it's almost half dead.
It might also be infected with disease if they feed it with tubifex worms.

Anyway, firstly, do a large water change of more than 50%.
Make sure the temperature of the tank is warm at around 27degC.
Betta doesn't like cold water.
Monitor its condition.
Look for any symptoms of disease such as fast breathing, lethargic, any white spot on the body/fins, skin peeling off, any abnormal growth on the body, clamp fins, etc.

Note: You may have to use salt later if it's really sick. (about 4 tablespoon of salt for 10 gallons).

Hi so the betta seemed okay in the shop, we got her a couple months ago. She wasn’t moving slowly, maybe a little pale though, but she got more colourful after having her a couple weeks. She was kept in a relatively small tank (less than five gallons) with 4 other females. Tank water seemed okay- this was in the shop.
I have checked the water temp, it is at 26 C but I can raise it if needed. I have done a 50% water change as suggested. Her fins are a little clamped. I know you mentioned tubifex worms risk carrying disease, although I don’t feed them tubifex I do occasionally feed them frozen bloodworms, is this okay? Thank you for all the help

 

[Circus]

As far as betta fish in a community goes, I had more success when I got the betta very young and raised them with other fish. My males are generally more mellow than my females when in a community. It is, in my mild experience, better to add a betta to a community than to add other fish to the betta's territory. One of my female betta, Jaws (named for her personality), is much more aggressive than any of my others. She was kept in a sorority and attacks any other fish not divided by a partition. The only creature she has not tried to kill is the snails.

 

[Lajos_Detari]

I think 26C is quite ok. But usually I prefer warmer.
Increasing the water temperature will help the fish to cope better with diseases.
But take note that if it's a bacterial infection in the tank's water, it may get worse at higher temperature,
Bacteria will multiply faster at higher temperature.

Most people claimed that their fish are ok with frozen bloodworms.(Hikari brand)
Take note that some people have serious allergic reactions to bloodworms even the dried bloodworms.
The allergic reactions caused them to have breathing problems/difficulties.
Even if you touch the tank's water, it can cause allegic reactions if you feed them with bloodworms.

But there is a fish breeder expert who argued that, "can anyone guarantee 100% that all the parasites cysts/eggs will die during the freezing process"?
This fish breeder did a lot of research to find out the best food for their fish growth.
Hence, in my conclusion, I won't feed them with bloodworms due to the risks.

 

[Retired Viking]

I agree with @Lajos_Detari I have avoided feeding my fish bloodworms.

 

[Lajos_Detari]

There is another problem with frozen bloodworms and fish foods.

If during the shipment of the frozen bloodworms/fish food, the delivery guys or the store's employee didn't store them properly in a freezer, the bloodworms will turn bad.
Even if the refreeze them, the bloodworms may have already turned bad.
So, this is another risk with frozen food.

 

[Circus]

I feed my betta a mix of new hatched brine shrimp (that I hatch myself), good quality flake, micro pellets, and the occasional blanched and shelled pea.

 

[ChloChlox]

Thank you everyone for the responses, I have been feeding my betta micro pellets, shelled and cut up peas but will definitely stop with the bloodworms if that also has a risk of carrying disease. If brine shrimp newly hatched at home work then I might try that. As for females being aggressive to other fish, I knew they could sometimes be a little aggressive but I guess I didn’t know how much they could be. I know someone said earlier they had more success with their Bettas when they were young, I was just wondering where you got them as I never know how old my betta is when I get them.
Thank you again for all the help

 

[Salty&Onion]

As I said once, even female bettas are not community fish. Even females do better on their own.