MSR and Platypus filters do a nice job of removing some tannins from the water you’re filtering. Tannins come from organic matter, like leaves, that break down in the water, giving it a "stained" appearance similar to tea. They’re not harmful in small quantities, but they do impart odor and a bitter taste to the water.
Over time, these tannins, like other debris, can clog your filter. They’re also quite sticky, which means they can get stuck in hollow fiber filters. Even with back-flushing, it can be tough to get them out.
A ceramic filter, like our MSR Miniworks, can be scrubbed clean of tannin buildup. This makes the Miniworks a great option if you’ll be in an area with highly tannic water. While you can still use hollow fiber filters and purifiers with tannic water, just keep in mind that tannins can accumulate over time. To help extend the life of any filter, try to find the clearest water source you can, and remember to backflush the filter.