I would keep the Via-Aqua and just bought a second one and chained them together if that was your goal. Also, BRS Carbon and GFO are not known the be high quality.. just low price. To me you don't save any $. I tried BRS GFO from a fellow reefer when I was out once and I swear I was lucky to get 2 weeks out of it. It all seems to balance out in the end when it comes to cost, you are just forced to do 4x as much work replacing BRS GFO vs RowaPhos. Same can be said for Chemi-Pure vs BRS Carbon, you will have to change out BRS carbon every 7-10 days vs 30 days.