It doesnt matter, the guys was probably saying give it a week so the tank has time to cycle but the .5g is going to have the same effects on the fish just more concentrated. I would move him right away, acclimating him if you can.
Also what other fish were you planning to put in there.
Edit: Yah now that I read that ^ maybe you should leave him in the .5g for a few hours because he might be stressed from the re-homing and I you might not want to stress him twice in the same day. I doubt it really matters but IDK.
Last edited by IonBaller07; 05-30-2009 at 04:54 PM.