Tested it:

400 watt hps
6" cool tube
6" inline fan (424 CFM)
12x12 passive intake with air filter

House is set at 75 degrees.

The cabinet is running at 76 degrees.

:thumbsup:

I am only exhausting the cool tube, it is drawing air from inside the cabinet, I did not give it it's own passive intake due to space limitations I did not think of previously. (cool tube was too wide for the dimensions I planned. So remember everyone design your cabinet around your reflector).