Ventilation Systems???

Im growing indoor for first time. My setup is in master closet, 8x8. Using a 400w Metal halide and rotating fans. The problem is, that my friend says I need a ventilation system. Where do I buy this at and how much would it cost?

You just need to make sure you vent (exhust) the rooms air. Get rid of heat, humidity, and stale air.

There are many ways to do this

What are the other ways? And where can I buy a red light for the flowering stage? Thx

Go to Amazon, HTG supply, LED Wholesalers, Your local hydro shop, a home depot and but an "inline duct fan, ducting, and a carbon filter". Hardware stores don't sell carbon filters though.

First you need to bring in air from another room or outside. Then you need to exhaust air out of the room, and best if it can go outside. You'll want your fan on the exhaust, and have the suction side of the fan mounted to a carbon filter. The intake can be passive. (no fan needed)

I'd recommend a Can Fan & Can Filter I've had a Can 50 filter and 6" Can fan running constant for almost yrs now and have never smelt anything outside my room and the fan is still very quite.

Without move info on adjacent areas, I can't really help with vent layout.

As far as the light, is your ballast MH only? is it magnetic or digital?