help me with my usage of lighttt!

hey there, recently i've set up a grow room in a empty room which has a heater and some storage. the room is most likely 20 feet by 4 feet. it has stone walls and a 600 watt hps ballast with one mother plant currently, while a different room holds several babies under cfl's. anyways for the time being the one plant is being flowered under the hps by itself. i know it has great potential for yeild and awesome bud so can anyone help me with using space and what is the best idea for the walls. the heater is in the way as well as some other tubes and such things that make it hard to spread mylar around. the hps is also hanging on a 45 degree angle which is mostly ontop of the plant. there are no heat issues and the only thing that gets hot is the reflector. so all in all, what should i do to get this room ready? light leaks into the other half of the room beyond the heater and also out an airvent but its not a security problem. just an issue of how much light am i utilizing? help me out guys n gals

oh and also when i say stone walls, i mean layered brick which is uneven and rough. i'm not sure it should be painted, it's not smooth at all. ok thanks i'm headed to bed so lets see what you guys think tomorrow

Paint it white with a fungicidal oil-based primer such as Kilz.
Your big challenges are going to be climate control: Ventilation of a long narrow space can end up feeling like a wind tunnel, lol, and you are going to need to lay down shipping pallets to get the pots up off the cold cellar floor. Cold, wet roots will KILL an indoor plant faster than you would imagine. Expect to be hanging ducting and fans to keep air moving around the plants.

If you only plan to run the 600, GREAT. Block off a 4x4 space in the end of the hall. This is an ideal footprint for a HPS600 anyway. Hang 2 layers of panda film, about 3 feet apart, as a light-lock set of curtains that will allow you to easily enter the area, but still not let light through in the dark time. Go into the room with the lights off, but the lights in the basement on, and check for light leaks.

Don't forget to raise up the plants on a pallet! You can also circulate air under there to help discourage pests and mold.

cant u put the silver mylar on the walls?

You still have to treat the cellar walls for moisture and mold spores. Cellars are a GREAT place to grow moldy bud, and you have to take extra precautions.

well thanks stinky, i'll work on that this weekend. i was thinking about boxing it kind of into the corner. the plants aren't on the floor actually but i had no idea that cold floors can kill babies like that! i'm glad you shared. so with the panda film you can just staple / pin it up on the ceiling and tape it to the ground? simple as that to make walls? and also when you said 3 feet apart, isn't that gap going to let alot of light out. well thanks for the tips! i'm going to go out this weekend get fungicide / paint / look for good quality mylar / panda film.. . . any local retailers of panda film usually? i'll makea stop off at my grow shop.

The grow shop should have panda film, and IMHO it is superior to mylar for a normal-sized room because when mylar gets dirty, fugheddaboudit. Panda retains its reflective qualities far better, and is easier to work with because it isn't going to tear like mylar does.
The gap- eh, picture when you go into a grocery store, and you have to go through 2 sets of doors? It's like that. A light-lock. You don't HAVE to do it that way, but you can be SO much more laissez-faire about tacking up the panda when you have that mostly-dark buffer room in between to negate light leaks. Panda has white front and black back. It's GREAT for this purpose.
Hint: Get a staple gun... :D

sounds good to me. i'll be sure to take some pictures once it's all complete and then you don't have to "imagine" the space at all. appreciate the help, until next time. :)