This work describes the first demonstration of a wavelength reuse wavelength-division multiplex passive optical network (WDM-PON) with employing passive modulation averaging for data erasure/modulation cancellation. We present a simple, low-cost, colorless bidirectional communication architecture that uses reflective semiconductor optical amplifiers (RSOA) and incoherent light communication. Successful error-free (BER<1e−9) simultaneous bidirectional communication has been demonstrated in links up to 30 km at 1.25 Gbps using 100-GHz channel spacing and bit- error rates (BER<1e−5) with 50-GHz channel spacing.