     If your little swimmer is putting on some weight, you're
probably feeding him too much - a problem that's easy to fix.
But there are two other possible reasons your fish is looking
chubby: abnormal fluid accumulation, or enlargement or
distention of body organs. If your fish's scales seem to angle
away from his body when viewed from above, then your fish is
probably not getting fat - he's getting sick.   Abdominal fluid
buildup, or "dropsy," occurs when a kidney tumor, cyst or
infection upsets a fish's internal electrolyte and fluid
balances. Bacteria (like mycobacterium or aeromonas), fungus
(like ichthyophonus) and protozoa (like coccidia) can all cause
kidney malfunction.  Another cause of dropsy is liver
deterioration, which leads to lower levels of albumin, a blood
protein. When albumin levels drop, fluid leaves the blood, pools
in the abdomen, and causes abdominal distention. Any organism
that destroys enough liver cells can cause this phenomenon.
Diseases such as mycobacteriosis (tuberculosis), no