i would suggest you plan to run the frag tank to the same system as your main tank, plan where you can put the frag tank for easy plumbing,
previously i tried to use my pico and qt as a frag tank but all my zoas frag died because i just din have the time to take care of all 3 tanks at the same time, evaporation and heat was the killer for the other 2 tanks, you throw in a fan to control the heat then it evaporates like crazy , dont use fan then temp is not ideal , big headache
so the frag tank that i gonna setup next week will run the same water as my system so i dont have to do any acclimatising for any of my frags when i transfer them over