Hi guys, have been out of the reefing hobby for 9years now. This time, I am looking to convert my freshwater to a fowlr tank with mainly angels, tangs and wrasse. Any gurus able to help give some tips and share any potential difficulties I might face? Current tank is 140x70x50cm with a 4ft sump. Will be reusing my brothers chiller for this tank. Another question. Can I reuse the sand and media for the freshwater?