Preventing Sump overflowing and flood

[elmizze]

Say if the water intake inside the tank has an overflow and underflow intake to bring the water in tank to the sump tank.

If the pump in sump tank stopped, the overflow intake will take in water from the tank until the lower mark entry on it. As long as the sump tank can hold the extra water, I think there won't be flooding.

What about the underflow intake?? Will it continue to take in water from the tank until the tank empty? Which means confirm whole room flooded liao!

Any bros/sis can advise on this?