Erasure errors can improve the efficiency of quantum error correction by revealing the time and location of their error events. In this work, we demonstrate erasure conversions and mid-circuit erasure detections in a single integer fluxonium where g, f states encode the logical states and the first-excited state e encodes the erasure state. The integer fluxonium suppresses direct f-g transitions and allows the dominant f-e transitions to be converted into detectable erasures. Furthermore, we identified a design space that nullifies the resonant frequency shift between the two logical states, enabling ancilla-free mid-circuit erasure checks using the same resonator employed for final readout. By discarding the detected erasure events, we achieved an 8.4-fold increase in the logical state relaxation time, a 1.38-fold increase in the Hahn-echo time, and a reduction of single-qubit gate error from 0.061(2)% to 0.030(5)%. Our results establish integer fluxonium as a hardware-efficient platform for erasure-error detection and conversion, while identifying the improvements required to realize an effective erasure qubit with high erasure bias.