Regarding whether or not to bolt it down, the instructions that I have been reading from the manufacturer state that it is to be bolted down to the floor over vibration pads but NOT tightened. Apparently that can cause metal fatigue (typically at the tank/support area at the top) from the vibration of the pump. The bolts are there to keep the unit from tipping over.
Yes, True. Once I had tightened down the nuts to get the anchors snug, I removed the nut and washer, then replaced the metal washer with a thick rubber washer. I put the nut on and brought it down to where it was just causing friction with the rubber washer. It should allow for slight movement without the nut coming off. I wanted to use a Nylon lock nut that was locked just above the rubber washer, but I did not have enough thread once I added the hockey pucks. I will have to see if they offer a slim Nylon lock nut in that size.