Need some advice on start up please.

Hi people.. sorry, am pretty new to such a hobby.. so please bear with me.. i really need some advice and help.

I'd like to know how much would a large tank cost? mmm.. like those that we see in Seafood centres? the large ones.. and what do i need to for set up? e.g the pumps.. filters.. and all..

And is it true that there's this device that will automatically sense the Ph value and treat it? or some electronical device to alter the temperatue and ph value or water conditions automatically?

I've seen some really awesome marine displays.. was thinking of getting one myself too.. but how much would the set up cost? for example.. the pumps and the devices and most importanly.. the tank... haha~


Really appreciate the help and avice.. thanks again~