I've been keeping fish for almost 15 years now, 3 of that was with a saltwater tank. At one time I had an 80, 2) 55s, a 30 and two 20s in my office.
I started with a 55 and went to a 75. My 55 was a half and half. I had about 50# of live rock and mixed the rest with tube worms, crabs, shrimp, snails, some hard corals and a couple fish. It was freaking expensive to just have that. The lighting will eat your lunch. I also had a water aging system running along side. Between the water monitoring, changes, lights, filters and keeping up with the RO water, it sucked. I loved the tank, it was actually in my office. But it got to be too much. I moved everything to a 75 at home and got it stable again. The 55 is set up now with some cool freshies. Guss my Hoplo catfish eats out of my hand (as does my other fish).
I started paying attention to the money. You could re equip yourself about once a year for the money I was spending. And it was hard to go on vacation. I was stressed the whole time. I was sure I would come home to a $grand$ in dead critters. The other reason was the collecting of fish & critters. Cyanide and shock is pretty harsh, there is a pretty low survival rate. I would rather dive to see them than watch one in my tank.
Oh, btw, my brother has the tank now. He just spent about $400 on replacing his lights (once a year or more). He has some high $$$ corals though.