What would happen to a coral reef if sea levels suddenly rose? ?

It would be destroyed; coral is a sensitive organism that takes just the right amount of light and warmth to thrive. If the sea levels rise, the shallow-water fish that fertilize the soil and eat the pests would be forced higher than the coral. Deeper water means less light, and in turn, less heat. A drastic water level rise would take away every parameter that coral needs to live, so it would just die, leaving only the already shed skeleton behind.

I’d have to say no because without oxygen in the water the fish would all be dead. so if you want to fish for dead fish, pick the ponds with the lowest oxygen concentrations.