no, if you wash your new sand really really well before hand and have it ready in containers all you need do is move your fish into another container - with a lid I wouldn't wish on anyone what's just happened to me (favourite fish jumped from an uncovered tank and I didn't see and now she's dead) then scoop out your old substrate - I find a net is the easiest way - dump it into containers then put your new substrate straight in. Do a decent sized water change to clear things up a bit and then set the filters going. Things should be clear enough for the fish to go back within the day.
Tank might be a bit cloudy for a few days whilst things settle down and it's worth keeping a close eye on the water stats too for a good week just to be sure you've not started a mini cycle but it's all do-able
Tank might be a bit cloudy for a few days whilst things settle down and it's worth keeping a close eye on the water stats too for a good week just to be sure you've not started a mini cycle but it's all do-able