I noticed my flowerhorns stomach got huge last weekend and he has been sitting in the corner of his tank. He seemed to be constipated and finally went #2 and it came out white and stringy. His stomach is back to normal now but he isn't eating anymore. He will try to eat but always ends up spitting it back out. And he spends all day sitting in the corner of his aquarium. I used metro and bifuran as recommended by the local aquarium but he does not seem to be getting any better. Any ideas? 