85g is more than big enough for a pair of maroons, but do beware that these are tough fish and you may be limited as to what you can put with them. I have a pair housed on their own - IME these are completely different fish when they're not constantly defending their territory. The only time I see aggression in my pair is when I have the audacity to step too close to the tank, or try to clean it!
Don't let their reputation frighten you, maroons are stunning fish with amazing personality, and as long as you find them appropriate tankmates you should be fine. They're not good neighbors for small, delicate fish; you want fish that can hold their own against a pair of pitbulls. Dwarf angels, tangs, damsels, wrasses, blennies and basslets would all probably do fine. I wouldn't house gobies, dragonettes, firefish, cowfish, or fairy wrasses with maroons.