You should think about a sump. Luv em. Makes maintenance a breeze and serves several purposes depending what all you put in it.
I buy all my carbon and most supplies from Bulk Reef Supply. They have high quality grade carbon. Best I've ever used. They have a video on U Tube that explains the different grades. Stuff you never think about. Also, I only buy Red Sea Coral Pro Salt. It's clears almost immediately when mixing and very little to no residue. Corals love it. Instant Ocean Reef Crystals are horrible. A lot of residue, hazy water, and kept the PH low.
That may be your problem with the hazy water and not the carbon.