You posted in another thread that your male dovii was 12 inches? Do you have 2? Man, going by your posts you have a TON of herps and fish! What are you keeping and what are you keeping it in if you don't mind me asking. Just curious.
Water changes will grow out a fish faster than anything. I read somewhere that a fish has growth inhibitors in its urine, some kind of hormone. Fresh clean water, nice healthy fish.