Well I got a response back from POR-15. Basically they said there are 3 things that can cause the product to fail:
1. The tank was not cleaned and prepped properly.
2. The inside of the tank was not dry enough prior to pouring in the sealer.
3. Puddling inside of the tank. If the sealer is too heavy in some areas the product will not dry properly and may fail down the road.
Then they suggested, "We offer a Heavy Duty Kit that includes our stripper which will remove our sealer." They then offered free shipping and handling.
I've had terrible results with POR 15 and now only have it done professionally. I know some people love it but it's never worked for me. I called the company to find out why it failed after a week and they said that sometimes on old tanks it's difficult to know what was inside it and that POR 15 might now work. I asked him to send me a replacement kit but I never heard from them or received a kit. I had to get it professionally removed which is only an option if the paint is shot (which it was). I'm not sure what you'd do to remove the liner on a nice paint job tank because they basically boil the tank whole.
So since I did everything I could to do it right the first time around, I don't think that I will be trying it again. Maybe get it professionally done. The paint looks ok from a distance, but not so great up close. It has started to bubble up in some areas. So regardless, repainting it is in my near future. I just have to learn how first
Im wondering if it would just be easier/better in the long run to just get another tank with less rust or attempt to still use this tank.
Where would I look to get the tank professionally sealed? Autobody shop? And does anyone know how much it typically costs?