In some very sandy water, like the Colorado River in the Grand Canyon, it could help to have something wrapping the float to help filter some of the silt. Normally, there is no need for anything, the float has some filtering built in. I have never had it clog on me but that is always a possiblity, with any filter, really. It can easily be cleaned in the field. The clearer the water source the less likely it will clog. Scooping water into a container and letting it settle would be desireable. In that case it may be better to wrap the float with a bandanna or filter the water through a cloth before filtering. The more sand and debris the more likley the filter will clog or at least pump harder.

The standard wide-mouth Nalgene 1L bottles will thread directly on the MSR filter. That is a nice design feature.