Well this block isn't going to work the way it is. As I was leak testing it a few minutes ago I was watching the water enter the block and the water is not pushing on the pins. The block fills up with water and just flows over top of the pins. Maybe a stronger pump is needed as i only have a 170GPh pump. I got some plans to work around these issues. But this block is shelfed for a while. Got a new one in the works already. Look for a thread called "My Micro channel block".