tiger barbs only get like 3in, and as long as they are in a decent size school i havent seen them mess with other fish, why in the world would a 4ft tank not be big enough for them? its not like hes keeping 50 of them, and OP could you post pic of your "texas" so we can see if it is indeed a texas or a carpintis as texas cichlids get much bigger and more aggressive than most carpintis