Tetras are acting weird

[GOO]

Hey guys, I am new here. Let me know if I am asking at the wrong places.

I had 11 neons and 5 rummy noses along with 2 lamp eyes killifish and a Betta in a smaller tank 25L and they were swimming happily and all that. And I decided to transfer all of them, including the substrates and water to a larger 45L tank. Then I added a pair of apistogramma cacatuoides last Saturday. They were all acting fine. And suddenly, last night, all the neons and the rummy noses are scrambling and hiding under my filter when I turned on the aquarium light (like they are afraid of something) and 2 of the rummies were playing dead (that is what I thought) and went back to swimming normally shortly after. When I turn off the light though, they went out from hiding and swim normally. Like they are afraid of something. But this morning, I found 3 of the rummies dead. However, the Betta, lamp eyes and cacatuoides are unaffected.

Before they act weird, I fed them white worm, which is their usual diet.

I have no idea what is going on. I could only suspect when I transferred the water and the substrate, I stirred out all those dirty things at the substrate and pollute the water. But I tested the water before I put all the fish into the new tank. So that should be fine.

Another reason I could think of is the introduction of the cacatuoides. But I don't see any aggression from the cacatuoides towards the tetras other than towards the Betta when she swim to his territory. Like just flaring to chase away the Betta.

So, any idea?

Thank you for your knowledge

 

[connorlindeman]

Hey guys, I am new here. Let me know if I am asking at the wrong places.

I had 11 neons and 5 rummy noses along with 2 lamp eyes killifish and a Betta in a smaller tank 25L and they were swimming happily and all that. And I decided to transfer all of them, including the substrates and water to a larger 45L tank. Then I added a pair of apistogramma cacatuoides last Saturday. They were all acting fine. And suddenly, last night, all the neons and the rummy noses are scrambling and hiding under my filter when I turned on the aquarium light (like they are afraid of something) and 2 of the rummies were playing dead (that is what I thought) and went back to swimming normally shortly after. When I turn off the light though, they went out from hiding and swim normally. Like they are afraid of something. But this morning, I found 3 of the rummies dead. However, the Betta, lamp eyes and cacatuoides are unaffected.

Before they act weird, I fed them white worm, which is their usual diet.

I have no idea what is going on. I could only suspect when I transferred the water and the substrate, I stirred out all those dirty things at the substrate and pollute the water. But I tested the water before I put all the fish into the new tank. So that should be fine.

Another reason I could think of is the introduction of the cacatuoides. But I don't see any aggression from the cacatuoides towards the tetras other than towards the Betta when she swim to his territory. Like just flaring to chase away the Betta.

So, any idea?

Thank you for your knowledge

Whats your filtration like? Also, what are your water parameters? (ammonia, nitrite, nitrate, gh, kh, ph. ) Could you post pictures of the tank?

 

[Rocky998]

Definitely answer the above questions but you so need a bigger tank ASAP... AT LEAST a 30 gallon long.

 

[Back in the fold]

If I had to take a wild guess I would say the shock of the move upset them.

 

[Rocky998]

Oh also, the betta may have murdered them... Just a thought. Bettas are very aggressive at times and in a tiny tank like that, that betta will kill everything most likely.

 

[Rocky998]

If I had to take a wild guess I would say the shock of the move upset them.

Yah that could definitely be a possibility. But don't you agree that tank is way too small for all those fish to coexist?

 

[Guyb93]

Il be honest , the tank is big enough for the betta . You can’t keep all these fish in a 10 gallon 40 litres

 

[Deleted member 149562]

Aquarium is far too small and the type combination/number of fish is lethal...even with the very best water chemistry.

 

[Lynnzer]

Logical thoughts here.
1st, the ones that were playing dead. Fish don't do that. Nor do animals either as it shows weakness and gives predators the idea that their next meal is just waiting for them.
If they play dead it's more likely than not that they were showing end of life symptoms.
Secondly, the dead ones are all the same species. That lays the foundation for a potential water quality issue that is not as problematic to the other fish.
The usual checks such as Nitrate, Ammonia, Nitrite and pH don't cever all the possibilities. There could have been a release of toxins in the substrate you changed over for instance. Too late to bring back the dead but I'd do a very heavy water change at least, JUST IN CASE

 

[Rocky998]

Nor do animals either as it shows weakness and gives predators the idea that their next meal is just waiting for them.

Possums play dead

But yah, fish don't play dead

 

[Slaphppy7]

Water params are key here...for all we know, the original tank may not have even been properly cycled...add the stress of moving, and fish deaths would be almost inevitable

@GOO, was the original tank cycled? How long was it set up?