Imagine a metre dia. disk of fibreglass with a 3" upturn and rollover at the edge sitting flat in a circle of bricks . Now imagine a 14" cube of fibreglass in the middle going down underneath. That's the sump where the pump sits. Over the years the outer edge of the catchment disk has sunk so that about an inch of water all round builds up before it tips over the edge of and back into the sump. I don't particularly want to dig it all out and reset it. Is there a product that I can use to spread into the catchment ring such that there is a slight fall from the outer edge back into the middle?
There is also a crack in one corner of the sump about 4" from the top - can I use the same stuff if it exists. Whatever it is it will have to be able to stick to shiny old fibreglass