Try this on your carbon

[Delphinus]

I agree on the ROX 0.8 as well. The only thing I can really say about it is that the smaller pellet sizes means you have to be a little more careful loading and unloading your reactors if you don't want a huge mess, also it seems capable of working its way through sponges so inevitably some will work its way into your sump but as far as a quality of carbon there's no alternative.

That article NorthernSeaCorals linked to just a good job of explaining the issue with organics and outlines why carbon is important even with good skimming.