How Many watts Do I Need to have a reed tank for my fish tank?

I have A 29 gallon fish tank and i want to get my tank into a reef tank. but i don’t know how many watts I need for my tank.

can someone tell me the watts I need?

and is this good enough to buy from ebay?

Coralife Aqualight 30″ T5 36w Double Linear Strip Light

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