I have a hog 1x. It took a few months to grow gha. I still have to use gfo to keep phos low. One thing about the hog, it will grow gha on the glass and when you brush it clean it floats into the water column which I don't like. I suggest going with the larger drops or surf if you have the space. Also I'm pretty sure there is more growth area than the hog.
Why decommissioning biopellets, has your experience been that the Ats will completely make bp's pointless?
Save your money bro and just make one of using pvc.. if u have a sump and the space.