You fish need room to swim, too
three of the fish are khuli loaches which bury themselves in the plants (I have about 7-8 fake plants) the betta stays at the surface, and the two guppies stick to the back, and the otos stick to the glass, so the entire middle part of the tank doesn't have anything swimming in it? I was thinking two small black skirt tetras to fill in the space to complete the tank, and it doesn't look crowded at all, almost totally bare. And there are enough hiding places for each of the eight fish to hide with no one seeing them at any time