Questions - Need some input

My incoming TDS is high. Extremely high. 750+ high. That being said my 4-stage does a very good job of getting it down. Usually averaging less than 30, sometimes 20. Well below the 5% accepted return. That's great for drinking water, but 20-30 TDS entering my DI is literally just exhausted a 10" BRS "Nuclear Grade" resin refill within 200 gallons. I am running this filter array:

5 Micron Purtrex sediment filter

5 Micron Matrikx+CTO/2

Carbon Block
1 Micron

...

I have an acrylic tank with plumbing on the back. In order for this tank to be useful to me I want all the plumbing to come up from the bottom, and have the tank sit flush against the wall. My question is, should I remove the bulkheads and patch a piece of acrylic over the holes, or plug the bulkheads? I prefer the first option aesthetically, but reliability is the key here.

Anyone have a source for medium/large colonies for sale, not just frags? I would like to get ahold of a few colonies of nice SPS to jump start the SPS collection in my main and frag tanks.