I start the frag tank build with a stand that i would make out of five 2 by 4's and two pieces of 48" x 24" x 1/2 inch plywood.
I used the Low Boy breeder aquarium from Zoo Med, which is a 50 gallon aquarium, that has an area of 48 by 24 inches, and is only 10 inches tall. They are reasonably priced around $135 to $150 depending on the area you live in. I used two AI 26 for lights and some old heaters that i had laying around.
For flow I am using one small hydor pump in the back and Jebao SCP-70M cross flow at the other end. I drilled to 3 holes in the back side of the frag tank, one line at each end of the back of the frag tank and 1 in the middle for Eclipse Overflow "Medium" that i plumbed to a Sump 20 gallon long DIY.
I used a Rio pump with a check valve, a Ice Cap protein skimmer and 2 Biological marine pure blocks in the sump. I am currently running a UFO light for the refugium and JBJ water auto top off for evaporation.