water change killed fish help!

[Tinadno]

So I have a 70 gallon freshwater tank with about 3 discus and a mix of 7 small tetra fish. Last sunday i changed all the filter media and did a water change. Today I came home did a partial water change after feeding my fish & ALL of my tetras died! And my discus look severely stressed. I don't know what the issue is. My nitrates & ammonia are 0 ppm. This happened right after the water change. I've never had this problem where 85% of my fish die after a change. I tried researching & only thing I could find is there may be too much Co2 in my tap water? Its winter here & has been really cold & apparently that has an affect on rising Co2 levels in tap water?? I could be wrong, but if anyone can help me out I would appreciate it before I lose all of my fish. thank you

 

[treemanone2003]

Did you remember water conditioner ?


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[Tinadno]

Yes and Stress relief

 

[philipraposo198]

Temp matched?

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[philipraposo198]

Test the tap

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[Coursair]

And in the future please don't throw out your filter pads. Just rinse them in used tank water or in dechlorinated water. You may have gotten rid of too much beneficial bacteria and caused an ammonia spike. Edit* I see you tested Ammonia.

And yes test the tap water. Sometimes water companies flush the lines or do things that may temporarily add strange things to our tap water.

I'm sorry for your loss.

I always run the water a bit before filling jugs/buckets.

Hope your Discus pull through.


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[Tinadno]

my filter pads have been in my filter since I got it. I've never thrown them out. I was talking about the carbon & I use Chemi-pure elite. Thanks

 

[Coursair]

my filter pads have been in my filter since I got it. I've never thrown them out. I was talking about the carbon & I use Chemi-pure elite. Thanks

Got it. ?


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