I Don't Understand It...

[ollyhtafc]

Two weeks ago i bought 9 white cloud mountain minnows, all was well untill i went away for the weekend and came back to find a dead fish, all the rest are fine, or they were, untill literally 10 minuites ago i checked my tank and there was one seperated from the shoal looking very down (the back end kind of slumped down rather than being straight), i checked back just now and it's dead.

I did about a %20 water change when i saw the fish looking ill (not sure why...just thought it couldn't harm.)
I do almost daily water changes of about %10.

The test kit i have shows nirtite, nitrate, ph, kh, and gh.Nitrite and nitrate are 0 the pH at 7.5 and gh is high (it always is..)

I don't understand why they died.I've been watching them breed ever since i got them.

 

[*Fishkies*]

Well according to the water stats you have posted your tank is not cycled. Your nitrate should have at least some reading. However your nitrite and ammonia readings should be zero. You could possibly be having high ammonia problems.

Are you working on cycling this tank?
How long has the tank been setup?

What size is the tank?
Are those white clouds the only fish in it?

 

[ollyhtafc]

10 gallon tank.
The tank cycled before i put them in there, however it was empty for about a week...could the bacteria have died with no food source?

The tank has been set up about 5 weeks/6 weeks.

And yeah...the only ones.

EDIT: Just done another test, nitrite is reading around 4ppm

I can't believe i've let this happen.I put a lot of research in! Just done a water change of around %40 to reduce the number.