HTOTM: FUSION
tier beginner: 0 qi (white belt)
tier 1: 20 qi (yellow belt)
tier 2: 50 qi (orange belt)
tier 3: 100 qi (green belt)
tier 4: 200 qi (blue belt)
tier 5: 500 qi (brown belt)
tier 6: 1000 qi (black belt)
tier 7: 2000 qi (2nd dan black belt)
tier 8: 3000 qi (3rd dan black belt)
tier 9: 4000 qi (4th dan black belt)
tier 10: 5000 - 9400 qi (5th dan black belt - 9th dan black belt)
tier elite: anything 10k qi and above (10th dan black belt and up)

Amount of QI needed is displayed next to the items as well, so if you're in doubt of how much QI you need for an item, it's best to check that instead of the item tiers.