The back is just a small 1 Gallon refug with an LED light. Would like to get something bigger, but it was a start.
There is a sump under the tank. The heater could go in there, but I put it up top until I was comfortable with temp and adjustments.
The sump is an acrylic thing I bought at Pristine Aq. with the balls on one side. I have a skimmer on the other side with the return pump.
On top I have 2x of the BeamsWork LED 48" lights. I got them for $100 for the pair on eBay.
The original light was a dual metal Halide and quad florescent system, but was in VERY bad shape.