While you're replying to that, here is a breakdown of your screen size and lighting:
8" x 8" = 64 sq in
64 sqin / 12 sqin = 5.3 cubes/day capacity - so you're probably at the correct size, depending on amount of feeding, but 5 cubes/day in a 100g is a TON of food, so I'm thinking you are under that - which is fine
Lighting:
CFL guideline for normal light, you need about 32W per side, or 64W total.
CFL guideline for high-intensity light, you need about 64W per side, or 128W total. This is a bit tough to do with a single lamp without burning the screen, so multiple lamps on each side.
LED guideline for normal light is one 660nm Deep Red 3W LED on each side of every 8 sq in of screen. So 64 / 8 = 8 Deep Reds per side (16 total). That's roughly 48W total, if you go by the "3W" rating on the chip.
LED guideline for high intensity light is one 660nm Deep Red 3W LED on each side of every 4 sq in of screen. So 64 / 4 = 16 Deep Reds per side (32 total). That's roughly 96W total, if you go by the "3W" rating on the chip.
Generally I would recommend something in between these 2 numbers that makes sense for the particular setup that you have. Keep in mind that this guideline is for DIY LEDs, 3W on star boards. So if you are going with a stock LED fixture, then shoot for right in the middle - so you would want a total of about 70 watts, or about 35 per side.
If you are making your own array, then find an arrangement of LEDs that give you good coverage and matches what you have available for capacity on whatever driver you choose. You will probably need one for each side, but not necessarily.
Also you can throw in Royal Blue chips, but I would use 1W chips for those, or wire a pair of them in parallel to cut the current down because they are very intense and can easily burn your screen in front of them. You only need one for every 8 reds, or 2 if they are 1/2 power or 1W chips.
HTH
Bud