The giant gourami is a deep-bodied, elongated fish with a broad head and a large mouth. It has a dark brown body with yellow or orange spots, and its fins are edged in black. The males have larger and brighter dorsal and anal fins than the females, and they also have elongated rays in these fins.
The smallest fish found in Lake Buhi is Pandaka pygmaea, commonly known as the Philippine pygmy goby. It is the smallest known fish species in the world. It reaches a maximum length of about 10 mm (0.4 inches) and is endemic to Lake Buhi.
The Philippine pygmy goby has a slender, elongated body and a large head with a blunt snout. The body is transparent, and the head and fins are yellowish. It is found in shallow water near the shores of the lake, where it feeds on zooplankton and other small organisms.