I bought my Lima at about 8 inches about 8 weeks ago and it is now topping over 9.5 inches (must have had a growth spurt) Mine is in a tank with an Oscar but I find if I put the food on the bottom while my Oscar has his mouth full that the Oscar will leave it alone for the Lima. I feed mine mostly beef heart which he seems to love, at least he eats a lot of it and it sure hasn't stunted his growth at all.
Mine is not real active with the bright light on, he mostly stays under the plants but if I dim the lights he will come right out and eat.
After the initial shock of him eating 2 of my 3 inch balas we now get along pretty good!
Good luck!