water filter holder

How I can unscrew the water filter cartridge holder?

I turned hot and cold water under the sink and then I went both taps open to depressurize the system. I have pulled and pulled and twisted the damn thing so hard that I pulled a muscle in his back. Has not moved a hair does not – one micron. What am I doing wrong? Under the sink is a filter with three cartridges. The worst part is, without filtration, the water can be "safe" but I would not give an enemy. It tastes like chlorinated algae. Yes, I'm doing it right. I think the tool is the best way to go. Thank you all. For the right way, " ie in the right direction. Thanks anyway, I bet people trying to unscrew the wrong path, and hopefully to help someone looking for this in the future.

I had the same problem with a Pur faucet attachment. I have one of those tools you unscrew the oil filter or somewhere else in a car. It is a metal strap handle and when Once it is pressed into the TULF. Or try using a piece of lining cushioned grip and large platform to open jars. I can purchase the roller transport and use at Costco for dozens of things. I do not have to use a rubber glove or shower mat. If the filter is small enough extension can use tweezers. Remember righty tighty, lefty loose. Then turn left to remove.

Brewing coffee with Moccamaster filter cone holder