iSpring FG15B-KS Premium Quality Super Capacity GAC and KDF Carbon Filter Replacement Cartridge for Direct Connect Under Sink Water Filtration System US21B & US21B-CPB, 10” x 4.5”

Ever since moving to a home with a well, I've been searching for a whole-house filter to neutralize the local sulfuric sediment which darkens the water and causes rotten egg smell. I've tried all sorts of filters from standard carbon block to fine pleat to basic KDF and found them all lacking in one way or another. But now I've finally found a filter which ticks all the boxes. Flow Rate - Much better than other KDF filters I've tried. It can easily run multiple sinks and showers simultaneously. Sediment Filtration - I don't see a micron rating anywhere, but it does a fine job stopping small particles which slip through my 40 micron spin-down filter. Smell Reduction - A new filter totally eliminates the rotten egg smell caused by sulfuric compounds in my water supply. Longevity - This filter is rated for 8-12 months and it certainly can run that long without any noticeable clogging or pressure loss. However, the sulfur smell began slowly creeping back in after about 6 months and became bad enough to trigger a replacement by 10 months. Design and Installation - Unlike other filters I've tried, the flow goes bottom to top rather than outside to inside. This means that the filter must be installed right-side-up, but there's only one seal to worry about because the bottom center is fully closed off. Overall this filter meets all my expectations at a reasonable price, and I'm very happy to finally have odorless tap water.

Installed this into a GE 10” whole house filter housing last week. So far no issues and the water is clear and clean. Chlorine was eliminated and the water feels better showering. Some call it magical but I hope it lasts a few months. So far so good and I’ll buy another one.

I've been searching for decent filters for years. I had one that worked okay, but then the company sold that division (GE) and it turned to cheap junk like most others I tried. Some of the other filters I tried left sediment through, odors, iron (rust) and some I think even added rust to my water supply. So far, this one is the best I've seen. Immediately the rust stains in the toilets stopped appearing (I had to remove them every week before, and I have city water so no idea where rust was coming from) and it has been over a month now with no reappearance. The design of the filter is really interesting so it maximizes the surface area while filtering and has elements built in that eliminate algae type gunk from growing in the filter. I checked the flow as installed new and it was slightly better than other filters when new (about 1 GPM more). These are supposed to last longer than the cheaper ones so I will test the flow at regular intervals and see if it degrades or not, but so far so good. Yes, this is more expensive than the last ones I used but if it lasts longer, continues to either remove rust or at least not add it, keeps algae scum from growing in the filter and doesn't disintegrate over time (yes, I had this before and was told by the manufacturer this is normal and shouldn't be harmful, but I don't like the idea of drinking carbon particles) then over time it may even be less expensive, and certainly give better quality and less maintenance, then it's the hands down winner. As I test this I'll update more if anything disappoints. As a side note I did contact the company with a few questions and their response was prompt and meaningful, as well as a few months later they reached out to make sure the product was still performing to my satisfaction. So far, quality all around. 6/29/2022 UPDATE: After using these filters for the last couple of years I had a failure of one that after 6 months released carbon particles into my water system. It plugged up faucets, washing machine inlet, internal solenoids of the washing machine and blackened toilets, leaving a layer of black "silt" in the toilet tanks. After contacting the company and getting past the initial "you need to flush new filters first" comments (I did state that it was in use for 6 months), the company stepped up and offered to replace the filter with a new one. Honestly I expected the typical run-around we've all experienced. Although there was a filter failure, I realize it does happen, and how it is resolved not only tells me that the warranty is real but also about the culture of the company. If they treat you respectfully and are willing to stand behind a product that means a lot.

I am loving how easy to replace these ispring filters are. My water tastes great and I don't have to worry about excess minerals, lead and Iron. Thanks Nick and John for your assistance.

Removed our string wound sediment filter and replaced with this iSpring filter. The hydrogen sulfide smell on the cold water side has disappeared. (Well water).

This doesn't remove smells even remotely. Not worth your money

I live in a place with the states highest chorine count in the water before I moved in my husband put a dinky filter on the sink I have added a 2 stage setup for the whole house and one for just the sink we get drinking water from. The water taste so much better.

Bought the Ispring whole house filter system with the sediment and carbon filter. I was told to buy this filter by Ispring after I complained about the sulfur smell still being there. A month and a half later I noticed my water pressure was reduced by about 50% or more. Upon inspection it seemed that this filter had stained up the inside with a blackish carbon soot all over the place. The original is carbon filter seemed fine. Took this one out and left the original in spot number two. Pressure is fine now.