Two Locations
Earlier ones had the tank under the shower seat. As I recall, the fix there is to cut a panel out under the seat for access, and then you can put some nice teak moulding around to cover the cut. Later ones had it under the swim step. That is where mine was. I purchased a Roto-Zip tool and got the little circular saw attachment to cut up the tank for removal. There is NO other way to get it out. It was put in before the deck was put on. I tried saber saws, cutters, etc. before I found the tool combination to cut it. I then took two 6 gallon tanks and siamesed them together to replace it. It isn't the best solution, but it gets you back the capacity and they are the largest you can install through the opening. Don't even think about trying to cut off the swim step; two tanks plumbed together is a much more reasonable solution despite the small hassle. Check the archives; I know there are articles about both tank replacements. If it still has the aluminum tank, it's toast.