We recently built a inground gunite pool. We were on a budget and the pb basically gave us no bells or whistles just a good pool. We have the standard Pentair lights. One in the pool and one in the spa. Just plain white bulbs. I have seen these color changing LED lights sold on Ebay and other pool supply stores. The price range from $50-$200. What does it take to replace what I have and install these cool lights? Is it a bulb that just screws into the existing housing? Does the whole thing need to be pulled out of the pool and rewired? I didnt really watch the guys put the lights in so I have no idea whats behind the glass. Thanks