i just got two of the gen-x pumps i turned a piece of brass to work with the outer nut that holds the barb on the pump then i tapped a 3/8 fpt into the brass worked great.
Please post that pic because I thought of doing the same thing.
Anyway the latest on this for anyone interested is this: I have tried every thread pattern known to man and none work. I spoke with tech support at DF&S the seller. They confirm their site and catalog lists the pump as 3/4 MPT. Interesting thing is their tech support says that their internal product description specifically says the pump is not compatible with external/hard pipe PVC applications. In order to use the pump you have to use the privided plastic nut which I do not want to do. They also measured the pump inlets in the wharehouse and they appear to be the same as what I got 1 inch. So mine are going back after much swearing and attempting to fix this without success. Make no mistake they are technically usable if you want to use the provided nut and hose barb but can not be hard plumbed without the nut.
Went to the site and found this:
Applications
Gen-X pumps can handle fruit juices, mild acid, mild alkalis, saltwater, nonflammable liquids, and other photographic and electroplating solutions.