Different parts of an octopus/reef  aquarium:

    - light
    - secure lid
    - closed-loop pumps (bulk of water movement)
    - sump (min water movement for chemical balance)
        - chemical balancing
            - protein skimmer
            - refugium
        - temperature balancing



Total equipment list:

    - 60-125 gallon rectangle glass tank                $200-$800 new
    - metal stand for said tank
    - 60-125 lbs Live Rock                              $240-$800
    - 10-50 gallon sump tank                            $0-$150 used