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.
Peptic ulcers are found either in the stomach (gastric ulcers), or in the duodenum (part of the intestines), known as duodenal ulcers. The most common symptom of an ulcer is a gnawing or burning sensation in the abdomen. Other symptoms may include: 1  Back pain. 2  Loss of appetite. 3  Bloating. 4  Nausea. 5  Weakness.