Common issues include:

• High organic load leading to increased BOD and COD.
• Accumulation of sludge and solid waste over time.
• Inefficient breakdown of organic matter.
• Foul odor due to hydrogen sulphide (H₂S) and ammonia.
• Imbalance or loss of beneficial microorganisms.
• Poor nutrient removal (Nitrogen & Phosphorus).
• Frequent maintenance and high operational costs.

These challenges reduce treatment efficiency and can lead to partially treated or untreated water being released into the environment.