Large Scale ATO System

[Ryan115]

Do you have room for a ATO reservoir in building 1? It would not have to be the same capacity but would need to be at least the same height as the main reservoir.
If these two are plumbed together, they will naturally keep the level even between them with no pumps required.
You could then use standard ATO pumps to keep each tank topped up independently, without having long runs and overly complicated systems.
I always find in this hobby that the K.I.S.S. principle and Murphy's Law are in full effect.

 

[Ryan115]

They generally have groups of their tanks tied into a common sump, which they keep topped off as a single system. And usually all their tanks are in the same room (often with the mixing station and RO/DI reservoir), making it all easier.

All of the stores I have worked in are the same, large walls tied in to common sumps.
Fish stores generally arent woried about ATO, as they are always having to account for the saltwater that is being removed during each sale. We always had to test the systems and add salt or fresh accordingly throughout the day.