what kind of ligthing system ,heater,beding,and filter whould be the best for my 30g orwhould a sump be better than a filter
Depends on what your plans are for the tank.
What type of animals are going to be in it, species, adults fry?
This will help determine what type of filtration and subtrate will work best for you.
What type of plants do you plan to put in it, plastic, high light, low light?
This will help determine the filter, substrate, and lighting.
Gonna be a hi-tech (CO2, Bright light) or lo-tech (no CO2, Low Light) setup?
This helps determine the type of filter, lighting etc.
What are the dimensions of the tank?
Mostly for lighting example I'd imagine a 4ft strip would be bigger than you would want, but also helpful for determining which plants and fish.