Those of you who never seen this type of fish, these are Marble Goby, in Malay we called them Ketutu and Soon Hock in Chinese. In Australia they called it the Sleepy Cod. Don't judge them by their ugly and scary looks, they are among the most popular and expensive freshwater delicacies in the Chinese community. A friend of mine caught 9 of these goby in the wild and gave them to me to breed. You don't need to have a zoology degree to breed these type of fish. I have installed a canvas pond with a total size of 5 ft x 7ft x 2ft for marble goby (1 feet of water). More ponds with the same size are now under construction. I use tap water with some anti-chlorine added for my pond. 80% of the water is change once in 2 weeks. I don't use RAS or water pump because there are not many marble goby in the pond (4 males 5 females)...not yet though. It is enough to splash the water once or twice in a day with my hand. A pond with this size could hold 50 to 70 marble goby at a time.