How are you draining the water from your tank? Maybe I missed that part? Are you automating that as well.
I have my 75 gallon sump in my garage, and ran about 30 feet of pipe to my DT, around my house and underneath my front side walk. I also have a drain pipe that runs to the back of my property probably a hundred feet that dumps the excess water/waste water. Only labor I have for water changes is throwing the salt in the container then flipping on two pumps. One to Drain then one to fill the new saltwater. Comes at the price of running a chiller though, which i would gladly give up because I don't get the floors wet any more inside the house doing water changes, and its very hard to manage a 2 year old while trying to do a water change as well!!!!!
I'm sure you will have good success with your set up you seem to think stuff out before you do and your tank is proof of it.