oh no, sorry to say he is very sick, there is a 'black spot' I will look up the treatment for you, the veins sticking out, Im not sure but I think it could be something quite bad.
Black Spot Black Spot, or diplopstomiasis, often follows the addition of new aquarium fish. All fish are susceptible, especially the Silver Dollar and Piranha. It is fairly easy to diagnose and treat.
Symptoms Small black spots on the body.
Treatment Black spot is generally easy to cure. There are a number of commercially available treatments and preventatives.
unsure about the veins but does it sound like this: Septicemia: A fairly rare to common in all tropical and coldwater fish. It is caused by bad tank conditons and is very hard to cure if not impossible. Bacterial Hemorrhagic Septicemia can be diagnosed by red streaking of the fins and body and once this disease progresses, ulcerations and body sores start to appear. There is significant loss of appetite, lethargy, loss of motor functions in the later stages of the disease.
Treatment: I recomend using Oxytetracycline Hydrochloride Powder obtained from a vet to cure this disease.