Family: Gobiidae
A semi-aggressive carnivore gobiidae from the major river systems of China, the Korean Peninsula and Japan — moderate care.
Rhinogobius giurinus of the family Gobiidae is an aquarium-kept Gobiidae. Semi-aggressive and carnivore; quality prepared foods with variety; regular frozen or live foods, it grows to 8.5–12.1 cm and prefers 18–26 °C water. Other Rhinogobius species in our database include Rhinogobius brunneus, Rhinogobius cliffordpopei, Rhinogobius flumineus.
That is normal goby behavior — they are ambush perchers. A healthy goby holds station on its stone, watches, and darts at food. Constant hiding, however, suggests it lacks cover or is being bullied.
Yes, provided each bottom fish has its own territory and shelter. Watch for squabbles over the prime cave, and add extra hideouts until disputes stop.
Moderate flow suits them and keeps oxygen high, but they also do well in gentle flow if the water is clean. What they cannot tolerate is warm, stagnant, dirty water.
Three to five years is typical in good conditions; their slow adult growth means a settled individual stays with you a long while.