I had to remove one of mine with this, it's called muscular necrosis. Copy paste: Shrimp with this condition is diagnosed with a white or milky discolouration of its back part, more specifically, the muscle tissue within its shell. This symptom is called Muscular Necrosis. Necrosis in biological terms is understood to be the destruction of one or more cells in a living organism. The result is an inflammatory reaction or decomposition of the surrounding tissue. Proteins produced by the decomposition of the cells will be released. And the milky white colour is seen in the tail part. Symptoms of muscular necrosis can be caused by Incorrect water parameters Bacterial infection Myxosporidien Stresses in big pH changes, lack of nutrients and oxygen deprivation, can also lead to cell death under certain circumstances. This milky white discolouration usually begins in the tail region and spreads in a few days towards the head until the whole rump is a milky white appearance. Treatment: Isolate the infected shrimp immediately, as muscular necrosis can be infectious. Generous daily water changes can often abate the disease. However, if the condition has affected the entire abdomen, a cure is no longer possible and the shrimp will die within a few days. Check water parameters in the main tank. Ensure all parameters are within tolerated ranges for the species. This includes temperature, pH, KH, GH,TDS, Ammonia, Nitrite, Nitrates, and oxygen levels. Sent from my iPhone using Tapatalk Pro