Hey,

I don't have a spare tank so I put the bag into my main tank and let it
sit for about 30 minutes. Then use a net to catch them and place them
into the main tank water. I have never really had a problem doing this!

S.
--
I sort of thought you may have done something like that.
What you did was to let the temp equalise, but the other water parameters
may have been
very different. Im not that good at explaining things. If your PH was out
just a little the shock
will kill the fish. There's lots of other things that they don't like to.

When I get a new fish I turn off the lights in the tank before I put the
bagged fish into the tank
after 10 - 15 mins I open the bag and add a little tank water into the bag
then 5 mins later I put
more tank water in the bag, if the bag is getting to full of water I pour
some water away down the drain
I never put any of lfs water in my tank. So by slowly adding tank water into
the bag the bag water
becomes more like the water in the tank and the fish don't get a massive
shock when I put them
in my tank.

adding new fish to your tank this way may help them survive.

David

no doubt someone will be along to post a link explaing this better.