I dont know if theres an adapter but the "dimmable" feature is usually on the ballast if it has it(dimmable is stupid btw, if your gonna dim your 1000w to 60% might as well get a 600). As long as your lights are air cooled properly you shouldnt need AC.
With a tent your size trust me when i say that youll be happier with 1000watters rather than 600s. Keep your ballasts outside the tent to keep temps down. And if you want more C02 make wine in your tent or buy Exhale C02 bags on amazon theyre like 25 bucks.