I admit, I probably don't do things the "Recommended" way. I just float my bag in the tank for 15 minutes to equalize temperature and then add half a cup of tank water every 10 minutes for an hour. Then I let em fly.
Never had a "shock" issue yet - but then again, I also use the LFS
's water to do my water changes, so my water is probably extremely similar to his on all parameters.
I also echo joy's statement of not adding so much at once. I have a 72G tank, and in the last 6 weeks or so have added 3 fish totalling about 5 inches of fish. Never saw any increase in any of the params. I acknowledge that is a ridiculously slow rate and that I'm likely overcautious, but fish are the one thing I've never really had a hard time acclimating/keeping