i have had xenias in my tank for the past 4 months and they are doing great. your flow sounds good but i would recomend keeping your temp no less than 79. also i have my light on for 12 hours(its a 24 hr lighting system). i have a heavy load of corals and fish in the tank but i add all the right things. i use kent; coral vite, coral accel, essential eliments, tech-i, and iron. I also use the b-ionc calcium and alkalinity buffers. And alternate feeding my corals zooplex, phytoplex, micovert,chromoplex, and marine snow. i feed my corals dialy and my clam, cucumber, and flame scalop twice a day, but i have a top of the line skimmer and filtersystem. my best recomendation is go online and read about care for them, its the best way to find out, peopel always come into my store wanting to set up a tank but expect to be able to do it without reasurch. i have always strongly beleved that if u want to be sucessful you need to read up.