I think this will give you a great start. Assuming your shelves are 4 feet wide, you can get 2 trays per shelf end to end or 4 trays side by side. If the shelves are 12 - 18 inches deep, a single 2 bulb fixture will do fine. With 4 lights on 4 shelves you can have 8 - 16 trays total. For 72 cell starter trays that is a lot of plants.
Wondering why you want to use 2 lights per shelf? The fixtures are fairly low to the trays and on my 4 ' shelves adjusted down, one provides quite adequate light.
You can drill holes thru shelves and install Eye or S hook screws. Then run chain or light rope down and attach with an S hook to the chain that comes with the fixtures. Adjust as needed. The chain comes in 15 & up foot rolls. Very small is fine cause you do not need much weight holding capacity. Just make sure to measure twice and cut them a hair longer than needed. Don't cut too short.
Which bulbs did you end up getting?
I do 12 on and 12 off myself on average.
You will also need a multiple outlet gizmo. Get one with as many outlets as you need plus 2 cause you will be adding stuff.
4 lights
heat mat
fan
That is 6 right there. I got a 10 outlet one and thought that was enough. Heh
Placement is key. Think it over. I mounted mine on the wall.
You may want to get a humififier as well. Not absolutely necessary, but I think it is impoortant.
Where are you setting this up? Basement?
