Temps are a $#%&#

Ok so I have a grow log in my sig I'm having a small issue hoping someone can help! So I set up my 1000 dimmed down to 600 over my small girls, I have 5 germ. Right now that are under 400w of floresant I got a 14x8 in a basement sealed off and as soon as I hung my black n white poly today temps shot up from the 74 I always keep to mid 80's and I don't like it... it has me reconsidering my whole set up! My cool tube is set up to pull are from a chimney I put up through the tubes and into the furnace and its ice cold but the light still generates enough heat to make the rooms hot! I have a 50lb co2 and I don't mind filling as I'm in welding so... but I hate seeing those temps!! As soon as temps started rising leaves started pulling away from the light and toward the ground I took down the decided I made from the Polly and my temps dropped back down ill leave it like this for now but when it comes time to flower I need the second room to veg my younger plants, I can't run AC so any other ideas!?

It's OK to run the plants at higher temps when using CO2. Low to mid 80's shouldn't be a problem, low being preferred. Do you know the CO2 PPM of the room and do you dose the CO2 or just keep the room at a certain PPM of CO2?

I have a regulator at 1500ppm my issue is I'm hitting high 80s low 90s!! I'm thinking alot of it is in use of the halide bulb I'm considering switching in my hps but in the mean time I turned off the co2 and put down my decided to slow basement air to flow freely like I had before my issue is as soon as things are rolling that's not an option as A: I need two rooms, and B: I HAVE TO KEEP ODOR IN!!! so... I'm trying to work the kinks out of my set up while I can before its too late ya know!?

Above 90 might as well shut down. Below 60 gets bad except at the end. Gal jugs of frozen water are good coolers