2.5x2.5x5 feet grow tent with 400w hps or 250w cfls?

This my second grow. As you can see, iam growing three plants and iam using a 250w cfl at the moment but thinking of switching to 400w hps since I wasn't too impressed with my first grow ( I got about half oz from one plant). My grow tent is 2.5x2.5x5 feet and I have an small intake fan and carbon filter and exhaust fan for ventilation. I don't have any issues with heat at the moment. I am thinking of buying a 400w hps for flowering but I worry about the heat. Do you think my grow tent is quite small to use hps? Is it worth it or should I stick to the cfls?

You should be good if your running a cool tube or vented hood running filter ducted to hood pulling hot air out of your tent. Do you know how many CFM your fan is? I ran a 4" 180 cfm in a 2x3x5 tent and it worked out. Summer temps got a little hotter than I wanted 82-85. You would be surprised if you got a vented hood or cool tube it will prob not be much hotter than your CFL.

My first grow was CFL and the reason I switch to HID is because of the small yeild CLF gave me.

Heat is produce by wattage, so that 250w cfl is outputting +250w of heat, also a 400w hps will output +400w of heat.

What I recommend is to buy HPS but make sure the ballast is dimmable.

I wanted to buy a 600w but when I installed it and had it running there is no way I can keep temps cool on that 600w, so I just run my 600w at 75% ballast (450w bulb), and I so far like the temps.

I am thinking of getting an hps 400w with cool tube but I have a question: I already have an intake fan, carbon filter and ducting for the ventilation of the grow area. Do I need to buy another intake fan and ducting to pass air through the cool tube?( i know it sounds silly but I am a newbie, this is my 2nd grow

No just use the one fan like I explained above.....you may need to hang your filter vertically instead to make room but one fan will work fine. Do you know how many CFM it is? Filter ducted to cool tube ducted to fan pulling air through filter light and exhaust out of grow area. Make sense?

Yeah, it makes sense now. Thanks rwbrock!!! I don't know how many cfm cause I live in Europe and we use a different system. It is 125mm(about 5 inches) and it's capacity is 330m3/h. It is quite strong, I think it will do the job!!

thanks again!!!