I'm not sure what kind of puffer it is, it's green with black spots. The tank is 50 gal and Ive been feeding him small pellets. But I do feed the other fish Krill and large pellets, but it's too hard for the puffer to eat them so he usually sticks with the small ones. We just did a water change 2 days ago. Currently the ph and high range ph are both around 8.2, ammonia and nitrites are 0, the only thing that is elevated is the nitrates (bt 40 and 50 ppm), which i have had a very hard time lowering...any suggestions would be great. We also keep live plants in the tank. Is the ph too high for a puffer? we have mostly africans, so that is why my ph is high. I didn't know too much about puffers when I bought one..but I do like them a lot. Is it possible that I need to feed it something else? Not sure why his color is fading...