Calcium Reactor recommendation for 120 gallon

[Bustyraker]

Getting tired of ordering 2 part every other month. I have 2 friends that have switched to calcium reactors and are loving life. What would you recommend for a 120 gallon. I have no experience with these

 

[427HISS]

Do you have a lot of stony coral's and coraline that are really sucking up your calcium levels ?

Maintaining a reactor can take a lot more time and expense,..... vs dosing.

 

[Zero Nitrates]

http://www.geosreef.com/product/geo-cr618-calcium-reactor/

I have this one on my 120. Seems to be working well. You can add a magnesium media to it as well as the crushed coral. Had it going for 3 months.