The cryptosporidium parasite is very resistant to chlorine and bromine, the chemicals used in pools and hot tubs for disinfection. This parasite is also very small. In fact it is too small for most private pool and hut tub filtration systems to remove.
The infectious dose of the parasite is low, and as a result it can easily be spread by swallowing pool water contaminated with the organism. Anyone who is infected should not swim in a pool while having diarrhea, and for two weeks after the diarrhea stops. Also, remember to try and avoid taking pool water into the mouth while swimming.
“Crypto” is not easily killed through a regular disinfection process and most filtration systems cannot remove the parasite. "Shocking" or "super chlorinating your pool or hot tub by bringing the chlorine levels up to 20 parts per million (ppm) will effectively inhibit the parasite. When “shocking” your pool or hot tub, take extra care to monitor the ph level in the water. Maintaining a pH between 7.2-7.8 is important to allow the chlorine to function properly. Test kits that measure chlorine and pH levels are available at many retail stores. Remember that swimming will be unsafe until chlorine levels return to normal (10 ppm or less), and do not use the pool for at least 8 hours while maintaining this level of chlorine.
If you have any questions or need further assistance, please contact us.
Updated 8/24/2007