Hey, I have the same query. I have a PR-22 that I bought as a combo. I am currently modding using a lot of Thermaltake stuff and I want to know whether I can disassemble the PR-22 and use the pump on it with a pump top as a stand-alone pump as I have separate reservoirs that I need to use. Can anyone tell me if the PR-22 pump can be utilised as a pump on its own. Cheers