Hey mama! Hindi ko sure kung 1 scoop to 1oz exactly kasi baka iba sa Nan Optipro variants, pero usually the ratio is written sa side ng tin, best to double-check there para hindi ka mag-guess lang! Honestly nag-panic din ako dito when my youngest started formula, pero once I saw the instructions clearly written nakita ko na sobrang clear naman. Check the tin or ask the pharmacist next time, they're super helpful dito sa PH with formula ratios.