fish dying

[bigfish10]

I have had my 55 gallon tank for a year, I check the chemicals weekly. All of a sudden last month fish started dying. I took the water for my local aquarium to test. Everything was fine. One week went by and again fish started dying. I change the water, but still dying. What am I doing wrong?
Bigfish10

 

[skipperdz]

what kind of food are you feeding....do your hands ever go in the tank after washing? or working on something? trace elements can get in the tank and cause a mess. sometimes fish just get stressed and die for no reason. i had 2 skunk clowns mysteriously die before.

 

[trigger11]

I think we would need more information to help really.
1. What are the water parameters? You say they are ok, however they may not be.
2. Was anything new added to the tank recently? New corals, any other fish, tank decorations, etc.
3. Are you still using the same kind of salt? Or just recently changed to a new brand. Etc.
4. What kind of filtration do you have? Have the filters been cleaned recently?
5. What kind of top off water do you use? Tap or RO?