There's really no need to change out bio-media, unless it is falling apart or something. Could cause a mini-cycle, especially if you change the sponge as well.
10 Gallon Low tech, Sand substrate.
Eheim 2211, and Aqueon Quietflow 10.
Finnex Stingray LED, 18" above substrate
Anibus, Narrow leaf Hygro, Christmas moss, and Anacharis.
8 Kubotai Rasboras, and 5 Blue Neocardia shrimp.