Welcome to Tropical Fish Keeping forum.
I moved your post out of the old thread to start its own thread, so more members will see it now. We have a couple members who have this fish, assuming it is Ctenopoma acutirostre, so they may be able to offer suggestions too.
You will find some info in our profile, click the shaded name to see that.
There are some other issues with your selection of fish. Tetra, danio and barb are all shoaling fish that need to be in a group of their own species, usually 6 is the minimum number suggested. But the limited tank size has to be considered too. And some of these get large, much too large for your tanks. There are also some water parameter issues, some of these fish need medium hard basic water (pH above 7), some need soft slightly acidic water (pH below 7).
At this point, i would refer you to the profiles, click shaded names: Neon Tetra, Giant Danio. The Clown Barb isnot in our profiles yet, so here is some info on this species, Puntius everetti: http://www.seriouslyfish.com/profile...veretti&id=182
It attains 6 inches and needs a group, so with your limited tank space i would consider removing this fish, the store might take it back.