Hello, New here and a relative novice at aquarium keeping. I have a 46G bowfront (36" Long) tank with 1 Three Spot Gourami, 5 Tiger Barbs, 4 Twinbar Platies and they've been doing well for a few months now (started the aquarium in February). After a few early deaths I feel like the tank stabilized and the water looks good (haven't tested it). My tank feels a little empty to me and I wanted to add an interesting fish to the group. I want to add a fish that doesn't require a school or companions of the same kind. I was looking into a Red-tailed Black Shark but I wanted to check with the forum if the shark would be compatible with my existing fish and the tank. Currently only have 5-6 fake plants in the tank, sharp medium size gravel, and have a HOB filter (Aqueon QuietFlow 30). If not the shark I was considering a loach or oto as well...any suggestions about what I can add or comments about my current setup? Appreciate any help!