Inline hose filters come in two forms that are bought for different reasons. A sealed disposable cartridge screws on, works for a season and is thrown away. A refillable housing takes standard cartridges and is serviced rather than replaced. Which suits you depends on how much water goes through it and what you are trying to take out.
Disposable cartridges
These are the compact sealed units, common in recreational vehicle and caravan use, usually combining a sediment element and some carbon in a small body. They are convenient, need no wrench, no O ring and no spares, and they suit intermittent seasonal use. Their limits follow from their size: very little media, so short life and modest flow, and no way to change the rating for a different job. Buy them where convenience matters more than capacity and where the season is short.
Refillable housings
A small standard housing on the hose line takes ordinary cartridges, which means the rating can be matched to the job and changed later: coarse sediment for irrigation, carbon for a pond fill, a fine element ahead of a pressure washer. Cost per change is much lower, media volume is much higher, and the housing lasts years. The trade is that it needs mounting rather than hanging on the hose, needs a wrench and a spare O ring, and is more to carry if the setup is mobile.
Flow, threads and connections
Check the flow rating: a filter that starves a sprinkler system or a pressure washer is worse than no filter, and small disposables restrict more than owners expect. Hose thread and pipe thread are different standards, so a housing intended for plumbing needs adapters to meet a hose. Fit a short flexible whip between the tap and the filter so the weight and the leverage of a charged hose does not work the tap connection loose, and support the housing rather than letting it hang.
What it will not do, and winter
It will not soften. Hardness is dissolved calcium and magnesium and passes through any sediment or carbon element, so spotting on a car or on greenhouse glass continues unless a deionizing cartridge is used, and those are consumed fast on hard water. And any hose filter left full over winter splits when it freezes, which is discovered on the thaw. Drain and store it dry with the cartridge removed. Our inline filter guide covers permanent appliance installations indoors.
Questions people ask about inline water filter for garden hose
Disposable cartridge or refillable housing?
Disposable for short seasonal use and mobile setups. A refillable housing for volume, lower cost per change and the ability to switch ratings.
Will it stop water spots?
No. Sediment and carbon elements pass dissolved minerals. Only a deionizing cartridge prevents spotting, and it is consumed quickly.
Why is my sprinkler weaker with the filter on?
The filter's flow rating is too low, or the cartridge has loaded. Small disposable units restrict more than most people expect.
Can it stay outside in winter?
Not full of water. Freezing splits the housing. Drain it, remove the cartridge and store it dry until spring.