Most of us started out with marine by trial and error cuz last time no src, dunno where to find information, impulsive etc. . as a result some of us kenna chopped by lfs or ran a system tt cant work. so i think u sld set aside a budget for ur tank, and ask fellow reefers to help you, they are all generous people.
i believe marine systems sld have a sump, and say u decide not to run one, be prepare to change water very often.
In fact the most impt equipments for a marine tank is:
1) the tank itself
2) the chiller
3) the lightings
4) the skimmer
Just these 4 equipments can cost $2000. .