1 Demodex is a mite that lives in small numbers in the skin of healthy dogs and cats without causing a problem. 2  Unhealthy dogs and cats, especially those with immune problems, Cushing's Disease, or on steroid medications can develop severe demodex infection.umans have their own form of demodex mite. The demodex mite is not rareâit is found in small numbers in the skin of most dogs and cats because the mites on their mothers normally travel to young pets shortly after birth.
- the hazard is growth of bacteria: 1  control measures are continuous recording of temperature (automatic) or visual control of icing of the fish. 2  the critical limit for fish temperature is 1 C. 3  a log on temperature and icing observations must be kept. 4  corrective action is checking of fish from period out of control, sorting and rejection of low ...
Two 40% water changes will not get you down to <20 ppm, it will only get you to 36 ppm. In most cases the larger the water change you can do the better, with one exception. Aquariums with high nitrate levels often have a low pH. A large water change on an aquarium with a low pH can cause fish mortality within 24 hours from condition known as pH Shock.