In its native form, (unaltered) the Gas Tank Renu process appears to be somewhat incompatible with a plastic flower pot.
The raw process as described, includes organic solvents, commercial rust remover, baking in an oven at 350-370 degrees, coating with liquid plastisol or PVC (one or the other is described in their patents) and then curing the coating by baking once again.
If there is some way to protect the plastic flower pot--an integral and essential part of the Pagoda fuel system--from the liquid plastisol or PVC, then this method might stand a chance of success. The other questions become what kind of plastic is the flower pot made of, and can it stand the chemical cleaning? Can it stand the drying and curing process at 350-370 degrees?
I surely don't have the answers to these questions, but this isn't the first time this has been brought up.
If there was a way to remove the flower pot, "renu" the tank, and then reinstall the flower pot, this sounds like a worthwhile process.