Piggybacking air tanks

I had a 60gal 5hp compressor, before I built the Big Shop.. I had a leak in the bottom of the tank, so the Manf. sent me another Tank..N/C..Problem was.. the pump would not mount to the tank the same...So I had a friend Fix/Weld the hole in the bad tank. Then , when I built the New Shop, I installed them side by side, inside the shop, and connected them. I ran a 3/4 black iron system , everywhere in my shop that I needed. Too Friggin Noisy inside the shop..plus was only 110, 5hp... So I got a 220, 7.5hp 80gal.dual stage IR compressor from my Tool Supplier. Then I built an insulated shed outside the rear wall of the shop, close to where the inside system was. I piped though the wall, and connected the new compressor to the other 2 tanks, disabling the old 5hp pump. So now I have a compressor, outside and quiet, connected to 2 60 gal tanks inside the shop.. So total of 200 gal storage.. Psi tops at 140..Works Great....