Choosing Calcium Reactor for 600 gallon sps system

[LokeLucky]

Hello Reefers,

Need your help in choosing right calcium reactor for my new build.

System will be sps dominant (90%)
Total volume is close to 600 gallon

I would prefer calcium reactor rated for more than 600 gallon since I have plans of adding another system to it in future.

Thanks

 

[cward]

I had great luck with a Geo 8X18 on my old SPS system with about the same water volume. I also topped off with kalkwasser at night using a Geo kalk reactor.