Wow thanks for that haze there was some really good info in your post

I've used a 1.2m tent before, I hadn't thought you would be able to put 2x600's in there.... It was really hot with my 1x600 but i didn't use an air-cooled hood just standard.

Is the temps really that much lower with a hood? I had decided to get 2x600 hoods but if you think 3 wouldn't be a problem in my 2.4m tent I think i'll do that instead.

Would really like to be able to get 200 clones together I think i'm going to have to grow trees this time around

edit: Do you know offhand what your temps would be like with just the extractor fan on but not your air-con unit?