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Jan 8, 2022
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Derbyshire England
I’ve had a tank up and running for 2 months now and I have 2 female bettas, 6 cardinal tetras and 4 cherry shrimp in a 48lt tank. My bettas where the first fish added and I’ve never had any problems with fighting or chasing …. Until I added my shrimp! Water parameters have been fine for 3+ weeks also.

Now my bigger female (blue) is flaring and chasing and has even pulled some scales off my other smaller female (red) I’ve gone out and brought an emergency 25lt tank to separate them. Personally it’s not not the tank I wanted at it’s quite tall but I’d rather them not die!!

I’ve put about 30% of my established tank water into the new tank and added tapsafe and a biological filter start into the new tank and then transferred blue into the new tank as I thought she could probably handle the stress better than red as she is currently beaten up and tired! I’m a bit worried about blue as I’ve literally just set this tank up in 2 hrs and put her in by herself she’s swimming up and down the tank and currently has stress stripes.

Is there anything I can do to help her? The new tank is set up next to the old one so I’m hoping she won’t feel too lonely. I’m doing everything I can to keep all my fish alive and as much as blue has bullied red I still want her to live.

Do I just need to give her some time to adjust ? Will she be okay going from community to isolation? Will I need to move over any moss/rocks to add more bacteria from my established tank?

I’m going to keep and eye on parameters everyday I don’t know if I’m worrying to much but other than the bullying she’s usually chill so to see her swimming about and unhappy makes me sad :(

Any advise would be greatly appreciated as I got quite emotional over all this as I finally thought I was on track! :(
take the old filter media and put it in the new filter
live plants and cover
add some tannins
Separating the two bettas was the best thing you could do. They reached a stage where one decided she was top fish and the other betta needed to be kept in her place. I would go as far as putting something between the tanks so they can't see each other, even if that's just a sheet of paper.

I agree with Sgooosh, move some of the filter media from the 48 litre into the 25 litre's filter - roughly in proportion to the fish. 6 cardinals are about equal to 2 bettas when fully grown so maybe a quarter of the media. If you can put live plants in the 25 litre that would also help.

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