Absolutly agree with Cannabolic on the CFL for ease. So many things to work out with HPS in that space while maintaining stealth. The fact that it's stealth implies one cant be opening it later all the time to fix stuff and with the potentials for heat problems it's probably best to go that route unless...
If you had your heart set on your design with a 400w in there with those stipulations in place I say an idea for a quick and dirty method is:
- Put a 6" to 4" reducer inline on both sides of the cooltube.
- Connect 6" instead of 4" vent ducting to the ends of the reducer.
- Put 6" bends internal to the box heading out the back left and right corners for intake/exhaust to the rear panel of the box using the two bends on either end of your current design.
The main thing is that if we use the 6 -> 4 inch reducers and correspondingly use 6" ducting throughout the rest of the systems, it should reduce the impact the bends would have to airflow significantly and theer definately shouldn't be any 'whoosh' sound with this setup at least (lthough straight 4" is still generally better than bent 6" (unless the bend is very wide, or increases very slowly and gradually over a long distance of course)
Light seepage without bends or some obstructing matierial would be obviously substantial and pretty much kill the stealth of the system.
Now...if 'I' absolutely 'had' to come up with something that I though was 'best effort' worthy AND it was also a 'labor of love' job where I had all the time and motivation in the world then I would:
- Mount the lamp in the vertical instead of horizontal configuration along the center line (from forwards viewpoint) of the dresser.
- As above use 4" to 6" reducers and 6" vent ducting
- Since the cooltube is vertically mounted in stead of horizontally I would place the exhaust vent at the top, with a 6" bend to the rear panel of the dresser again along the centerline with no bends left or right before exiting.
- Pipe the intake straight from the floor with no bends (which I see is raised in your design which makes this a good option).
- Fabricate a three sided 'open' box underneath the dresser to surround the Intake vent coming out the bottom (which since it is 'straight' it will seep quite a bit of light) while placing the 'open' potion of the box facing the back of the dresser. Paint to box flat black for a little extra to prevent light reflection (some light would get out but it shouldn't be too noticable).
- Though I'm not certain how I would accomplish it specifically, I would try to work into the design some sort of slider system to adjust the height of the lamp without having to diconnect and reconfigure the venting itself. (Perhaps it might be possible by using excess ventilation piping on both the top and bottom side of the cooltube and then, by running thin, maleable, but durable wire cabling along the vent duct and securing it to it to the ducting well enough that when the cable is reeled in it collapses the excess ventilation piping accordian style while it simultaneaously pulls the cooltube/lamp and conversly expands the other venting using the same method.
There are drawbacks, like having to turn plants often as they stretch to the centerline mounted light source but that could be handled outside the box with pulleys attached to plates or circular pieces of wood under each plant which could be all linked together (via a belt, chain, whatever underneath them) which is inturn linked to the pulley string outside
What do you think?
