Yep. You especially want luck buffs (from food, etc), not just a good luck day, because the probability of a room being a treasure floor is 1% + daily luck/10 + luck buff*1%, i.e. the daily luck adds +/- 1% to the chance, and then you add 1% for each point of luck buff. So if you have, say, a perfect best luck day (+1%), then magic rock candy increases the chances from 2% to 7%. If you only want treasure floors, you can also add ginger ale for another +1%, or +2% with Qi seasoning. Luck rings also increase the probability by 1% each.
So if you want an autopetter, your best chance is to get a bunch of ladders (the best way is to trade jades for ladders at the desert trader on Sundays), stack as many luck buffs as you can, and then go down the floors with your ladders. If you don't get what you want, reset the day and try again till you get it.
@Boo1972 you're probably talking about Haboo's 28-hour perfection run video? In that case, IIRC he was basically just stopping when the magic rock candy ran out, since it doesn't last the whole day. (He didn't have ladders there, so he was just doing a normal SC run with explosive ammo. If you're using ladders, you'll most likely run out of ladders well before the rock candy runs out.)
Agreed, whether or not a floor is a treasure room is decided when you enter the floor. Even if you reset the day, the specific floors that are treasure rooms, and what they have, won't be the same.
Source:
@BlaDe talked about this while he spent 20 hours doing the strategy I talked about above to get a red cabbage seed from Skull Caverns (pre-1.5.)