Weaken without killing
Throw a Rot Box only when wild HP is low. If you KO the wild Brainrot with an over-powered move, you lose the chance to capture it and only get partial Tong coin drops.
Right box for the level
Throwing a Rot Box at a Level 18 Epic wastes Tong coins. Upgrade to Gold Box as the shop unlocks so your boxes match the level cap of the Brainrot you are hunting.
Sell duplicates
Selling a caught creature returns 5x more Coins than simply killing it. When you need cash fast, grab a stack of Rot Boxes, catch low-level Brainrots nearby, and sell them for a quick turnaround.