Man that Palmer's is a sweet coral, I used to have a good sized colony of it, but for the life of me I could not photograph it blue, it looked blue to my eyes under my light, but unless I used a flash on it the picture always came out purple .. guess a really old camera with horrible blue sensitivity.
And awesome job with the water tank, I did that a couple years back and absolutely awesome fill that bugger up with RO/DI, throw in salt, mix, and you're good to go whenever you need salt. Unfortunately mine was a 1/2" wider than the door opening... so I had to take the frame off, move it in, then put the frame back up.
Interesting bit about the bacteria though, I always did worry about that due to the RO/DI being too clean, but figured adding salt would be enough of a shock to kill off any bacteria, and the constant salinity change when you refill it would work well enough.