Help for tetras dying off.

[skybleu]

Hello Bros & Sis,
Need some advice regarding my nano tank fishes.
Currently have a CO2 planted nano tank with mixture of Monte Carlo, Brasiliensis and Riccia.
Introduced some cardinals into the tank after acclimatisation of 30mins using drip method.However, the cardinals started to die off one by one after 2 days.
Not too sure what may be the reason for it. Left with 3 of the 8 I introduced into the tank.
Anyone here encountered same problem? I have about 20 cardinals in my tank.

Thanks for all advice.

[mUAr_cHEe]

Did you test your water parameters? Any tell-tale signs of cause of death? Knife on their back maybe?

[skybleu]

Will test parameters when I get home.
Single fish started to stray away from the big group, after some time erratic swimming behaviour then went upside down(died).

[mUAr_cHEe]

It seems weird. Maybe they were already dying from something from the LFS since your old fauna is still doing ok.

[jiajuen900]

How large is the tank and how long has it been set up for?

[bennyc]

have your tank have been cycle proper. google nitrogen cycle aquarium for more information.

if yes, mostly likely like bro muah chee said, this is an unhealthy batch of tetras.

i will suggest you monitor the situation 1st before adding more fishes. to prevent more cross contamination to "new fishes"

[mUAr_cHEe]

If you all have been following skybleu, you will note that he does have an established nano tank running for a while. I am giving it the benefit of doubt that he is referring to that tank. Then again, there are chances where he is setting up a new tank.