Need Help Hanging Lighting

[Jaws]

So i've got 3 very heavy DIY LED pendants (about 40 to 50 pounds each) that I need to hang from the ceiling of my fish room. I want the 3 pendants to hang on a track that will allow me to slide the lights right or left so I can basically make room for my body to get in between any two pendants to work on the tank. I'm just not sure where to start looking for such a product because of the weight I'm looking at supporting plus the rust factor involved with a saltwater tank. Any suggestions?

Thanks in advance.