All fish died?

[Angelduran58]

I have a 40 gallon tank it's been up for about 1 year the tank was perfectly healthy and I had done it's weekly 10% water change on Thursday and today my mom calls me sayin all my fish are firing so I rush home and I find everything dead :,( any clue to what might of happened???
I had
2 angels
1 bala shark
1 Black ghost knife
3 molies
2 guppies
And a Pleco.

 

[jetajockey]

Hi. It's hard to say exactly what the problem was without more information. Testing the water is the first thing, just to get an idea of what the toxin levels are at.

Usually though for everything to die at once, something might have contaminated the water, maybe an aerosol or something else.

 

[Mogurako]

When posting about sick and unhealthy fish make sure to add pretty much every detail about your tank (water parameters, temp, filtration, ect...) before posting other wise is drags out finding the answer to your question/s.

Also make sure the heater didn't crack introducing live current into the tank. That's the only thing I can think of off the top of my head besides what Jeta mentioned.

 

[BillD]

Live current in the tank from a cracked heater doesn't generally harm the fish. A weekly 10% change isn't very much. It may have been enough when the fish were small, and the tank was newly set up, but is probably not enough for a mature tank with adult fish. A 10% change even without dechlor would not kill the fish. As stated above, a sudden death of all fish has to be the result of some type of contaminant or toxin.