one plant per 60 gal pump??

pretty much i have 2 bubble buckets ready to go and im still wondering, should i get another 60 gal pump for my other bucket?? i know u can use one for both buckets but my main corcern is the amount of air each plant is gonna receive. i tried using the one pump for both and the amount of air significantly decreases. ive heard somewhere the more air the better....but i dont want to use unessesary electricity. if its gonna produce more yeild then id get another pump no problem. any suggestions?

 

thanks