Luckily mine was only rusted to within about an inch of the top, so I filled completely and just let the foam roll out. I ran it as low as possible and tied a small screen to the end of the (+)-it was destroyed.
Just wondering how often you had to top it off?
I wanted to get the whole inside as mine was rusty all the way around, how was yours on the top?
I'm thinking of reversing the process with a piece of galvanized anchor bolt as the "interior" cathode to "galvanize" the tank interior. I've tested it and it works. Heres the test pic. Its hard to see but the zinc is firmly bonded to the cleanest portion of the 3/4 strap.--Lee