Fish Dying Rapidly

[PhatRam32]

Ever since I changed filters from a tetra whisper filter to my aquaclear filter, I have had 4 fish die in the last month and a half. Not sure if this is a coincidence or not.

I tested my water and all levels seem to be within normal range except for the carbonate hardness. All of a sudden it is through the roof at 240 mg/L. I perform water changes every 2 weeks and never had a problem until lately.

I have had a swordtail, female betta, 2 gouramis due recently. My other fish (zebra loach, dojo loach, pleco, pictus catfish, paradise gourami, powder blue gourami, and silver gar) are doing just fine, luckily.

Any suggestion and advice would be greatly appreciated.

 

 

[Blondielovesfish]

What size is the tank?
Would you be able to post the exact results please?

 

[slschmid]

If you changed the carbon in your filter as well it could be due to the fact that there are no more " good" bacteria in the filter cartridge

 

[the_lock_man]

Did you move the filter media from the Whisper to the Aquaclear?

 

[Jessman]

it could be because the aquaclear filter is 'too clean', meaning it has no good bacteria in it, like others have said

 

[Skies]

Unless you used the old media from your old filter, it seems you've just restarted your tank cycle.