[Buckeye Field Supply]

Carbon blocks do a much better job than GAC in this application - so much better that the GAC isn't really worth having in that position.

If you don't have chloramines in your water, you only really need one (1) good quality carbon block. You can lease the other (third prefilter) housing empty. I wouldn't use two 0.5 mic blocks because you'll lose a bit of pressure with each. If you DO have chloramines, go:

1. 1 mic sediment
2. Catalytic GAC (CGAC is much superior than plain old GAC)
3. 0.5 mic block

OR

1. 1 mic sediment
2. 0.5 mic block
3. 5 mic block

Russ