Green Terror Growth

Question
I have a 55 gallon tank & 4 green terrors that have the tank all to themselves.  I have had them for about 9 months now and I am a little disappointed in their growth rate, especially since they have such a large area all to themselves.  I would really like to see them all reach their maximum size, I think that there is only 1 male and 3 females.  Is there any special kind of food, feeding pattern, and/or routine that I should use to get them to their full potential?  I feed mainly food sticks at the moment, which always worked great for making big Oscars & Sevrums.  Your help will be appreciated.

Answer
Hi Ryan,
 Growth rate is a function of several things: food is only one of them.  Water temperature is also extremely important: fish grow faster in warmer water.  

 The frequency of water changes is equally important.  The more often you do water changes, the faster they will grow.  The reason is that when you don't do water changes, metabolites (the products of the fish eating and burning up food energy) build up in the water which actually retard growth.  
 Fishes grow fastest on "flow-through" systems, but these are typically impractical for most home aquarists. For a home aquarium, changing 25% of the water once a week, every week is a good compromise.  

-- Ron
  rcoleman@cichlidresearch.com
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