Hello all, i have a question or two about my grow set-up. Im using a DR-60 (This is my second grow).Ok so i was considering two ways to pull the hot air from the bulb and also vent the hot air in the tent.Im using a hydrofarm 400 watt sunburst<enclosed ballast> switchable hps/mh light.I made a modification to the hood by making a hole on the top of the unit and sealing on a 4in flange plastic toilet ring(ya I know but it works excellent) to hook my ductwork to for pulling hot air from the bulb,I also made a modification to the tent for the flange to stick out of the top of the tent. Now on this tent it also has a 4in adjustable to 6in hole for running ductwork. So my first thought on the setup followed by my second thought. Heres what im working with. 6in. Active Air 400 cfm inline fan with a hydrofarm fan speed controller. A Carbonaire filter 4in. rated for 200 cfm with 16lbs. of activated carbon.I was told the filter would be fine with the fan dialed down, it would just hurt the life of the filter but I plan on replaceing it after this grow to the next size, Its what I could afford. 25ft of insulated duct. Also when I plug the fan into the controller the fan has a buzz noise to it, if I don't use the controller theres no noise except rushing air.Any ideas on how to eliminate the buzz? Looking to ake it as quite as possible. DR-60 tent measures 24x24x55.2 inches. 1. My light has a protective glass heat lense that I bought with it but with my first idea I believe I would have to remove it. Is that ok to not have in there or is it a good idea to have it inplace? Anyway I was thinking of attaching the ductwork to the top of the hood which is on the outside of the tent running it thru around 10ft of duct to my carbon filter which is attached to the fan and exhausting thru another 10ft of duct. On this example I would have to remove the glass lense to pull the air from the tent over the light and thru the rest of the setup. 2. Leaving the lense in place and connecting to a Y adapter which will be paired with another piece of duct that I will run thru the top hole of the tent I had mentioned earlier,So 1 piece of duct would be pulling heat away from the bulb while the other is pulling heat from the room both using the same fan and filter setup. Can anyone please give me some advise on which would be a better setup? Any and all thoughts welcome. Thanks.