one thing i have had recent problems with was an inline fan that shakes or vibrates. this can cause hoses connected to your lights to shake loose or even rip, eventually causing an air leak which will defeat the purpose of having an air cooled system. it can also cause loud vibrations which is the reason i created a housing for the fan;
this is pretty much what it will look like when it is done. the bungees help reduce the sound by 200% so if you can hang it you will be much happier.
first start by measuring the fans height and add an inch or two then cut the wood for the box. if you are using 6" hose then cut a hole on two of the boards that are 7" in diameter, these boards will be the end boards.
next set the fan on one of the boards and mark where the holes are on it, then drill them and mount the fan to the board (do it now, makes it much easier).
once you have done all of above go ahead and connect the hoses.
also you need to cut or drill a "V" in the side of the board where you want the power cord to go through.
after that you can go ahead and put together the last couple sides and you have a brand new silencer box for your inline fan.