6915. Causes of shell rot

 

Shell rot (ulcerative shell disease) in a young red-eared slider is a bacterial or fungal infection that damages the outer keratin layers and deeper bone of the carapace or plastron. [1, 2]

Primary Causes of Shell Rot

• Poor Water Quality: High levels of ammonia, nitrites, and dense bacterial or fungal loads in dirty water directly seed infections through tiny abrasions on the shell. [1, 2]
• Inadequate Basking Conditions: Lacking a proper dry basking area or sufficient light access (10–14 hours daily with an 82–90°F / 28–32°C basking spot) prevents the shell from drying out completely, fostering pathogen growth. [1, 2]
• Physical Trauma and Injuries: Scratches, chips, cracks, or bite wounds from tank decorations, sharp stones, or tankmates create entry points for bacteria and fungi. [1, 2, 3]
• Insufficient UVB Lighting: A lack of UVB rays leads to Vitamin D3 deficiency and poor calcium absorption. This causes  Metabolic Bone Disease which weakens overall shell integrity.
• Nutritional Deficiencies: Diets low in calcium or Vitamin A compromise the turtle's immune response and the structural health of its scutes and bone. [1, 2]
• Improper Husbandry / Confinement: Keeping young turtles in small tubs, buckets, or water levels without adequate dry-docking options or filtration leads to chronic skin and shell softening.