Buddy if your in 12-12 you want lower humidity. High humidity in flower can pramote pest and mold on the bud. Low humidity is better than humidity that is too high. What are your temps at now? Do you have any inline fans that could be used to suck the hot air out of that room? Do you have a garden stor around that sells hoods and lights? I would look for a air vented hood or go with the cool tube to get some heat out of there that may be coming from that light.
Well good luck
Adieu