Overfeeding is the number-one cause of high nitrate levels in aquariums. Overfed fish produce much more waste than normal, and when more food is given than they can take in, the uneaten food rots and produces even more wastes. Keeping too many fish in a tank also leads to problems with accumulated wastes.
Symptoms Caused By Esophageal Ulcer. One classic symptom is a dull or burning pain. It is common with all forms of peptic ulcers. The affected person may feel the pain radiating within the areas starting from the navel up to the breastbone.
Common symptoms of an ulcer include: Heartburn-like symptoms. Abdominal pain (or stomach pain) -- especially at night. Loss of appetite. Bleeding ulcer symptoms may include dizziness, vomiting blood, and blood in the stool (seen as dark-colored stools). Some people with an ulcer may not have any symptoms.