[Nickj]

I used flowliner but any of the slow cure expoxies would do the same.
It is a pain getting it all round the inside of the tank but a look with a little scope says I only missed a few tiny areas which I think will do fine.
It's also white so it much easier to see where you are with the stuff unlike caswell which is clear.

Just leave the tank to dry off for as long as you can. Mine was sitting in my shed over the summer where it got and stayed nice and warm, plu there was a dehumidifier making sure that the air was dry (so sucking out more moisture)
I had a pack of frame screws so used them to prep the tank inside once dry. Put them in and shake lots then wonder where that last screw has got jammed!!