vivosun 600 watt digital ballast

https://www.rollitup.org/t/first-ever-grow.1012128/#post-15458505 I’m noticing a lot of discoloration and yellowing , any growers out there with advice ? Quiet a bit of details in the post any other information just ask !

Hey all..hope someone can give me some super fast input as this is time sensative issue as I nees to have a new light ordered STAT!! I am looking to buy the Vivosun 600 watt digital ballast. But dont know if I should buy the regular one with normal reflector OR should I buy the air cooled one...