Is this a standard 75 gallon? Do you have the dimensions?
Will this be a low budget build? You can either do it right, do it to get by for awhile?
Then there are emergency(optional) items like universal power supplies.
Things to add control such as full tank monitors and controllers. The amount you put into a tank can really add up.
There is a lot of research and not to sound rude, but it's difficult for us to go through an entire list. But we can start with basics....
Tank
Skimmer(optional)
Mechanical filtration(semi optional)
Lights(led or halide)
Live rock or dry live rock or dry rock
Sand or no sand
Power heads
Heater
Thermometer
Auto top off(optional)
Test kits(calcium, mag, alk, ammonia, nitrite, nitrate, phosphate)
Dipping solutions
Salt mix
Quarantine tank for new live stock
I'm sure I left some things out. But that is a start
