Aqua C released the RX-1 Calcium reactor back in December 2007. Since then it has been getting mixed reviews, however we didn’t pick it up when it was released. Specs include: – 8.25″ x 9″ footprint, 16″ tall, Giant media chamber, Reverse flow, Recirculating CO2, pH probe holder, Eheim 1250 pump, JG fittings throughout., Sch. 80 PVC and unions throughout, Large union lid for quick and easy media addition, abdSMC valve for precise effluent control. Retails for $429.