No offense, but I think the chain link look tacky. Steel wire would be more hideable. These steel wire are available at Lowes or HD. They are not adjustable and you'll have to cut them each time you want to re-adjust them.
You might call AquaTek, and ask them if the hanging kit for the Gieseman are adjustable or not. I don't know how much that cost, probably $20 to $30 per kit. You can mail order some Hanging wire for the Red Sea Prizm Power Compact Pendant from the manufacture in Houston. Cost is about $5 for each set plus shipping. These kit are semi adjustable. You might be able to find some adjustable steel wire kit from toy hobby stores, but I woulnd't know where to look.
If you find any adjustable steel wire kit, please let me know. I need a set for my Reef Optic myself.
Look at all those live rocks on the beach at Florida's state park!