Salts CaSO4 2.4g, CaCl 5.0g plus a quarter tab campden. Whirlpool FO hops for 30 min starting at 75C.
Based on boiling 7.25 gallonsliters at 1.050 for 30 minutes, this will decrease your wort by 0.50 gallonsliters, bringing your after boil OG to 1.053. You wanted an OG of 1.061. It looks like it will be under.