Since I had to solve some leaks and a cracked pump volute, I decided to completely rework the plumbing on my return pump so that it was simpler and hopefully would prevent noise and vibration from traveling out of the Fish room. I hadn't turned the pump on yet, but I figure that if I plan to kill noise, it is a good thing.
Here is the new setup. I didn't want to have to do the quick 90's after the pump, but with the space and angles I was left with coming out of the wall, I couldn't come up with anything else.
Here is how I am dealing with pump vibration. I have it on a thick foam pad (about 1" thick) then onto a solid board which then sits on another 5/8" of open cell foam. It's all bolted to my bench from there.
After all that, I still got a very very very slow drip out of the threaded fitting going into the bulkhead. I should have used silicone rather than just teflon tape when putting that together. About 1 drip every 5 minutes.