I did a mix of the Arag alive indio pacific black (you can find it at the link Riverserver posted) and Carib Sea Aragamax. well mixed, it gives a nice overall look and pretty much everything I read pointed to one of the two. The dried aragamax does really well in my brackish tanks and makes PH maintenance a breeze!
I used just the aragamax in the refugium along with a good amount of live rock chips (I took a chunk of rock and whacked it a couple of times to break it down). A handful of crushed coral in the intake section of the sump to get a good bubble tower and it seems to be doing good!
I am curious what luck people are having with GARF Grunge as I may add a couple pounds of that when I switch my sump from the 10 current to the new 20