All my fish died after water change

[BigQFan]

So, this happened to me once last winter and now it's happened to a friend of mine just last night. She did a small water change(4-5 gallons in a 46 gallon bowfront) and within 3 hours lost over half of her fish. Did a water test immediately and nitrite and ammonia were 0, nitrate about 40 ppm. It's a newer tank, maybe 6-8 weeks old and she is frustrated.
Yes, she uses Prime in the new water and matched temps fairly close.
Anything we are missing?


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[ImACoolguy]

Could the chlorine content have changed in the tap water? Sometimes water companies play with it throughout the year.


Caleb

 

[BigQFan]

That occurred to me as well but it was a Sunday night. Makes me think that all the chlorine would have been flushed by then but it's definitely a possibility. Is there a way to test for chlorine?


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[ImACoolguy]

That occurred to me as well but it was a Sunday night. Makes me think that all the chlorine would have been flushed by then but it's definitely a possibility. Is there a way to test for chlorine?


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Best way to know is call the water company and ask.


Caleb

 

[BigQFan]

Thanks


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[coralbandit]

I don't think it is a chlorine issue.
4-5 g in a 46 is only10%.
Chlorine would have to be pretty high IMO.

For testing for chlorine you just need OTO solution.
2-3 drops in 5-10 ml water .
If any yellow is shown then some chlorine is present.
I got my OTO from a breeder/chemist friend but pool supply store or Ebay sell them.

 

[katiekelsey]

That happened to me last year. I spent weeks trying to figure out what happened. I finally realized I had been cleaning my house and used glass cleaner. I had washed my hands but not good enough. I must have had a small amount of glass cleaner on my skin and that is very toxic to fish. I am more careful now.