Please help! I've had my betta fish, Narwhal, for over a year and I love him so much! This afternoon I noticed he is all white and his fins color is gone by the body! I don't know what to do! I've moved him to a quarantine tank with aquarium salt. I don't want him to die. I read it may be caused by a tumor but the thing is I don't see a tumor on him! I attached pictures. Please help!!!!!