I know you want to begin with beginner/hardy corals, but you have to think of the future; otherwise, you end up spending more than you need to in the long run. The main problem is that T5 retrofits in 60" range come in Very High-Output, which means the bulbs are being overdriven and primarily used in tanks over 24" in depth. You could try either a Tek2 4x80w (better spread), IceCap 6x80w (better peak), or a combination of IceCap 6x39w and IceCap 6x24w V-HO
. The first two should allow you to keep anything imo
and the third soft corals and lps
unless both were V-HO
As for sand, the Fiji Pink is very nice and you'd need roughly 200lbs. of sand (80lbs/cubic ft.).
In terms of drilling the tank, you can make the closed-loop as intricate or simplistic as you want. For a simple design, have a 2" hole drilled at about the 16"-17" mark and run multiple lines over the top. You could even incorporate an OceansMotion device and purchase a Reeflo Dart Gold for the dedicated pump.