What size air stones/pumps should I use for my reservoirs? One is 40 and the other is 70 gallon. Would a good pump with a 48" air diffuser in the 70 and a 36" in the 40 work ok?

What types of other nutes/additives should I consider picking up. Only have calmag+ and AN bloom and micro atm. Superthrive and some b1 be a good idea, or maybe Liquid Karma instead? Don't want to overdo anything, but want to have anything I might need on hand ready to go. Already plan to pick up some final phase