Pegging is a great way to place coral frags in your reef and be able to later create space between them by quickly relocating pieces to different holes. Affix corals to frag plugs with glue, putty, toothpicks or rubberbands, depending on the species and its characteristics.
When aquascaping a new tank, pre-drilling 1/4″ holes in the the rockwork will provide places to put pegged corals as desired. Drill shelf rock or bigger rocks as you rockscape — it’ll be very handy later when you add more and more frags.
Ecotech Cg 30ml: http://www.melevsreef.com/node/1631
DD Aquascape putty review: http://melevsreef.com/node/1668
Music snippet from Ross Bugden. https://www.youtube.com/channel/UCQKGLOK2FqmVgVwYferltKQ