Well we just moved into a new home and the pond there has been running for 8 years, well since i have played around with it, it has started leaking. I was going to drain it and re coat it anyways. So my problem being, the old coat well not come off, i have got some off, but some sealant still remains, could i just seal over it? Also does the surface have to be dry b4 i paint the coat on, thanks.