Laura,
I haven't replied to this because I'm not familiar with AP cages and I'm also not real familiar with using Flexwatt. All I can do is throw a few ideas out here and see if it gets you anywhere.
First - Reflectix is usually used to cover the outside of cages and helps hold heat in that way. For instance: I would probably lay it on the top and let it drape over the ends and back wall, trying to get it to lay flat against the surfaces, taping it to the cage if/where needed. You might have to cut out for vents.
Second - Flexwatt will raise the ambient temps somewhat but I don't know if it will raise it 10 degrees. About the only way I think it would raise it that much would be if you were to cover the majority of the bottom of the cage with it, as in - the length of the cage. However, you might be able to use Flexwatt in the grooves and let that area become the hot end and use the RHP to maintain the cool end temps.
I may be wrong but I think you can tape Flexwatt to the bottom of the cage where there aren't any grooves. I don't see why not. The only difference that I can think of without seeing the cage is that this area is thicker than the grooved area and may not heat quite as efficiently but it still may be enough.
Another option is heat mats like "rottenweiler9" mentioned. I can understand your reluctance to use them due to the frequent urination problem but if I'm not mistaken most of them are waterproof. But, I can still understand reluctance.
I don't know if another RHP would do the job or not. If I were you I'd call Pro Products and talk to them about it.
I think Flexwatt would be the least expensive of all. Even if you had to line the majority of the cage bottom with it. But then again, money can sometimes relieve headaches.
Hang in there!
Mike
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Due to political correctness run amuck,
this ol' hillbilly is now referred to as an:
Appalachian American

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