I'll start by saying you won't need a reactor yet, for one xenia is a soft coral it doesn't use cal or alk
. Your waterchanges with high quality salt will provide the necessary nutrients until you have a good bit if lps
, your gona is a lps
but I will warn you they are very hard to keep more than 6 months they require very stable parameters. As far as a good cal reactor, you need to get an idea of how much coral your gamma have and how much your willing to spend, a double chamber reactor with bubble counter and place for a ph controller will save you alot of headaches. Bulk reef supply has some good calcium reactors and you can order your co2
tank, regulator, and solenoid all from the same place instead of paying shipping at two different places.