It's not the flow rate itself that is important but rather the exposure time to the carbon.In other words if you had a long and large volume of carbon, a high flow rate would be fine as it would still get a lot of exposure time but a small short amount of carbon would need a very slow flow rate to be effective.
It's not the flow rate itself that is important but rather the exposure time to the carbon.In other words if you had a long and large volume of carbon, a high flow rate would be fine as it would still get a lot of exposure time but a small short amount of carbon would need a very slow flow rate to be effective.
That's only partially true. The idea is to get as much water through the carbon before two things happen, its pores are clogged due to capture capacity being reached and more importantly before the bacteria found in your tank explode due to natural carbon source now in tank and render the carbon considerably less useful which typically happens in 3-5 days or so. After that its ability to remove dissolved organics heavy metals and other material drops dramatically.
That said slow and longer is fine so long as there is active flow through the carbon. The more active typically the better so while stuff may not be captured immediately it will in the long run (3-5 days) eventually get caught.
