We’ve been asked this question countless times by people who have become frustrated after spending a lot of money on various shower filters that don’t give them the results they’re looking for. To soften water, you need to use a large volume of resin, much larger than would ever fit inside a filter the size of your hand. Even if resin was ever put inside a filter cartridge, it would be such a small amount that it would only soften the water for a few minutes then it would never soften water again since you wouldn’t be able to regenerate it. Many people have been misled because when some of these companies set up their listings they include keywords or phrases such as “soft water”, “soft water effects”, “soft skin”, etc. and you’ll end up on their site or listing thinking that’s what their product does. But it doesn’t. And many people aren’t aware of what soft water really is or that filters don’t in any way soften water or that there’s more to improving your water quality other than just filtering it. Unfortunately, there are companies who take advantage of people and aren’t always truthful regarding what their product can do (and some of them don’t really understand what the product they’re selling does). They want to sell their product plain and simple. You can challenge them and ask, “If I use a hardness test with your filter, will it show it’s removing hard water minerals like calcium and magnesium?” If their response is “yes” and you take a chance and buy it but find out otherwise, will they pay for return shipping if you decide to return it (which could be expensive international shipping) if their posted return policy says they won’t? Even the largest internet retail company in the world (no need to mention their name) won’t do anything about the companies who sell on their site and falsely advertise what their product can do. (This company doesn’t even require their sellers to show where their products are being shipped from.) So, it’s hard to know who to trust and what information (especially on the internet) is true or accurate. But we as consumers must do the best we can to do research and educate ourselves prior to making purchases and we need to do what we can to be sure a company is legitimate. Otherwise, we may end up getting ripped off. Luckily there are companies that exist who really care about helping people and giving honest and accurate information, and we are one of them. We will always answer your questions thoroughly and give you examples or information to backup what we’re saying. For example, if you aren’t convinced that a shower filter isn’t capable of softening water, we’d let you know that you can use any hard water test kit and it will show no difference in the hardness of water after you add a filter. Only a softener can do so. And only if it’s a softener that’s regenerated with salt water (works via Ion Exchange). Two ways to soften the water in a shower: install a whole house water softener or a portable shower water softener, like the ShowerStick: ShowerStick