Newbie at this

Good morning

I just bought a 150 gallon saltwater tank from someone I have a few questions maybe you can help

1. I have I have a water system in the house not osmosis but the question is can I still use it in the water I mean to add into the new aquarium?

2. I have a bunch a rock that they gave me with the tank they say it will come live in my need to add any Live rock or is this fine?

3. I am going to do a coral and fish setup any suggestions on lights how many I need etc.

They are very expensive out there maybe there somewhere or someone that is selling the lighting please suggest ?

4. Are there any local Reeves sites or on Facebook where you can swap buy sell things with people for aquariums

5. My filtration system is as you see below there is also a chiller

Do I need to get rid of all that and get new ?
Do I need to take it apart and clean it ?

There is some little round balls with the filters what are they

Do I need to buy more balls or different stuff to put in there please advise

Sorry for all the questions I guess when you're a newbie it always happens LOL

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