Thanks for the response. 

Curiosity question; do you notice a speed difference if you have say a 1Gb bloom versus the full 8Gb bloom you are running? Or is it the same speed no matter how large/how many h160s the bloom contains?

I will try and start small; create a smaller bloom first (30M h160s), run it, see if I notice a speed increase and make sure I understand/get the process right.