I've come into (begun renting) a pool that appears to have a disregarded fiber optic lighting system. It appears to have circumference lighting under the rim and 3x side lights that all end up coming out of the ground together by some loose electrical hookup. The fibers are all joined together and capped in what looks to me to be a wet splice (like you would use for a submersible pump electrical hookup).

I'm wondering what I need to do to light the pool up given the equipment present, and since based on some quick research it looks like pool rated "illuminators" run $600-700, is there a DIY solution I could rig up (I'm not afraid of bit of electrical engineering)? Anyone who has a similar setup or who has trod this path before?