ive had three grows all exclusively with DWC and im just gonna throw in my two cents. A lot of people opt for black buckets so that no light can penetrate but they are more likely heating their water unintentionally by doing so.

get a COMPLETELY opaque bucket. try to go with lighter colors with the most white as it will reflect heat BETTER. a bucket with a white top and black sides you will still be raising temps. also a tiny hole for gas exhaustion so that youre not throwing a lid on a boiling pot.

i stuck a 2$ film thermometer for a fish tank on the outside of my bubbbler to watch the water temps and i never got over room temp by more than 2 degrees F( 72.)