I have a Malibu Two (not the XL version) and haven't been able to find a way to fit a bait tank when I have my son with me. I usually strap a crate on the back for extra storage and added some rod holders to the back of my seat. I tend to use a bait tube hooked to the side of the kayak to store some bait in. I've also tried a bait sled dragged behind the yak but found that it slowed me down too much.
I went with the Scotty tracks on both top rails and use those to mount my bait tray, fish finder and Scotty rod holders.
I've been very happy with it as I use it for kayaking with the family and fishing and the Scotty rails have made it so I can set it up in several different configurations.
