For a 180 gallon with 35 gallon sump SPS dominated mixed reef, would the CR612x2 be the right choice or would another model with an auxiliary reactor for effluent be more effective?
Thank you for your consideration of GEO calcium reactors made in the USA.
You could go with either of two models whichever fits your space requirements better the CR612X2 or if you feel you may upgrade later the CR618 coupled with SMC415.