Very aggressive liquids can damage o-rings and check valves over time. For example, if your pump leaks from the tap, you can replace o-rings yourself. See the Troubleshooting Guide to diagnose and solve the usual problems. Purchase either maintenance kits for periodic repair of tap o-ring or full o-ring replacement kits here.
If you have had your pump for several years and some of the internal parts (i,e., check valves which are not user-serviceable) have worn, or if you incorrectly used it with the wrong fluid, the factory can refurbish it for you rather than throwing the pump away. This is good for the environment rather than filling up the landfill with plastic and less expensive than purchasing a new pump. Please call us at 866-639-4628 and we can diagnose the issue over the phone and make a recommendation as to what you need.