Im making a tutorial on the whole house filters and the mistakes made during the process. I would like to say thank you to everyone - especially boatboy24 - for gathering all this information up. I have been on the phone with a technical support with Pentek the manufacturer to get to the bottom of this. I would recommend the following ( recommended by the manufacturer for wine filtration ) FILTER HOUSING - 158116 - WRENCH- SW-1A BRACKET - 244047 FILTER - 1 MICRON = P1 FILTER - 5 MICRON = P5 Barb fittings - 1/4 npt to 3/8 barb all can be found at http://www.filtersfast.com. except for the barb connectors I do sell them on my accessory page if you can not find them locally. It has been recommended to definitely mount the housing to something solid in order to properly tighten it down. Next index your housing top and bottom after hand tight (with a marker or paint pen - see above post for pics at this time ) Install filter until the index marks align up properly. That will tell you that your housing to O ring is properly sealed. Teflon tape the barb fittings that screw into the housing - do not over tighten The difference between the P-5 and the PD-5-934 is the 934 has a plastic tube liner and it is much harder to align up the marks - the P5 has open ends on both sides( without the plastic tube reinforcement ) and that is what creates your seal as the housing is tightened down it will literally makes its own seal in the cartridge itself. It should not damage your housings, even if you install it wrong, unlike the PD-_934 I hope this clarifies any problems with the use of the whole house filtration system - there will be a better tutorial later - I just wanted to get the information out there as quick as possible. Here are some pics, the top one is the cartridge with no filter - hand tightened and indexed The 2nd picture shows a P5 filter that is tightened with wrench ( notice the index marks ) The 3rd picture is the pd-5-934 filter that is tightened with wrench (notice the index marks ) The 3rd one will definitely pull air in the housing that could not be seen by the naked eye. I would like to thank Boatboy24 again for the great pics !!