Fish Dying

[bunniebabe13]

Hello,
I have a 3 gallon tank which had 3 white clouds and 1 golden algea eater. I cleaned the tank last night (pulled out gravel and plants and such to wash). I made sure to keep about 1/2 of the old water to put back in the tank after I cleaned it. I put the tank back together and put my fish back in... everything was fine. When I woke up this morning, one white cloud and my algea eater was dead... no signs of why they would be dead. I had only had the Algea eater for less than a week. Obviously, I am a little scared about my other 2 white clouds. Do i need to do anything except keep a close eye on them? I took the Algea eater back to the store and they gave me my money back, they tested my water, which was fine. What could have caused these deaths?
Thanks,
Kim and the WC'splish and Bath

 

[WILDER]

To be honest a 3gal is not big enough for them fish it's only a tiny tank, all you can keep in that is a betta, do you run a filter, shock to changing the water stats, you should never remove the gravel completely you do a gravel vac, plus if you have no filter the bacteria colony would of been in the gravel.

This thread might help you.
http/www.fishforums.net/index.php?showtopic=126217