Mini Sponge filter (corner) - https://www.amazon.com/HIKARI-Bacto-Surge-Foam-Filter-Mini/dp/B00TTBLDXY/

Air pump kit (includes all necessary accessories including check valve) - https://www.amazon.com/FEDOUR-Aquairum-Outlets-Aquarium-Bubbler/dp/B0BVLH4MKG/