Just want to put added emphasis on these darn discountfilter filters and how damn fragile they are. When posters say not to over tighten that's an understatement. I tightened mine less than one revolution past finger tight and the housing still cracked! It's odd because the plastic (acrylic) is beefy where the threads are located.
When I was doing the salt water thing I would have to tighten the filter housings (RO/DI unit) substantially more than these pentek (sp) filters after changing a DI filter out.
Use caution! I wouldn't tighten much past 1/2 revolution after finger tight (seriously).
Hope this helps...
As has been repeated here at least twice and elsewhere, DO NOT OVERTIGHTEN THE TOP OF THESE FILTERS. Use vaseline on the seal AND the threads. You should only have to hand tighten it. Period. There should be no leaks at this point. If you reef on it you're going to have a bad time. Not only are you likely to crack the housing but TAKING IT APART WILL BE NEXT TO IMPOSSIBLE, even with a wrench. This is a known issue with the acrylic filters and a half hearted effort scanning the plumbing DIY forums will have you a believer.... Sorry for your accident cobra. Discountfilters will probably replace it though.
Always use teflon tape on the threads of the barbs. This is what it's made for. They shouldn't leak. Remember guys, these filters are designed to work at 50-80 psi on household water systems. Leaks are not acceptable.