If the plecos came from Walmart they are more than likely commons which will be way to big for tank. The tiger barbs should be in a group of 6 or more to keep there aggresiveness down. The Mixed fruit tetras are dyed fish. I won't go into my feelings about them. http://www.deathbydyeing.org/ All of your tetras are probably black skirt tetras so compatabilty between them shouldn't be an issue. You have a typical beginner mistake stocking issue going on. You need to figure out which fish you would like to keep and start over.
