I recommend the CR-5 over the CR-6. I have found from personal use that the dual chamber units are ineffective and require the recalculating pump to work harder then necessary. The second chamber does not successfully buffer the the PH and aragonite in the chamber does not adequately dissolve. The CR-5 with center spray bar is in stock, 10LB CO2 tank, pH meter or controller as well.
After researching, I decided to go with the MRC CR-6. Now I am discouraged by this email from a retailer. My gut feeling is that there are no CR-6 in stock and they want to make a sale. Can anyone give an opinion either way?
After researching, I decided to go with the MRC CR-6. Now I am discouraged by this email from a retailer. My gut feeling is that there are no CR-6 in stock and they want to make a sale. Can anyone give an opinion either way?