Low flow through dual-reactor solid block GAC?

[Ironic_Water]

I just put in a basic manifold from my return pump that connects to a dual chamber reactor Tee'd off from my return line. The first chamber just has some biomedia (porous rocks), and the second has a solid 5 micron carbon block filter (the same filter I have on my well system for my house).

My Sicce SDK 7 has a hard time pushing water through the carbon black. I was wondering if I could install a ball valve above the manifold to choke water flow going to my return nozzle in my display tank to force more pressure going into the carbon block?

Or, should I ditch the solid carbon block and go for the more inefficient, but higher flow, loose carbon?

 

[bushdoc]

Go for loose carbon