When I move tanks that size, I usually just remove decor, drain the water about 2/3 down, and just carry the tank with the fish still in it. I know it's not the best/safest way to transport a tank and that it should be emptied completely, but it has always worked for me. No guarantees though. I'm not gonna tell you that you should do that because it is risky, but that's personally what I would do.
Your safest bet though is to empty the tank of everything, bag or bucket the fish, and move them that way. Since it's only a few blocks, I wouldn't worry about air pumps or anything. I've taken fish on 3-4 hour moves dozens of times in buckets without airstones and they are fine. Like M|L said though, the key is not overloading the bucket, which shouldn't be a problem for you.
