I have been looking at the SK5000 and noticed that the micron size of the fleece noted on the filter details page is 32 micron. But all the replacement rolls I have seen are only 20 micron. The max flow rate is listed at 1320 GPH. Since that's also on the filter details page I assume that flow rate is if your using the 32 micron fleece. So what would the flow rate be using the 20 micron fleece? And is there 32 micron fleece available somewhere? Most filter socks being replaced by roller filters are 200 or 100 micron. 20 micron seems awful small and would most likely shorten the life of the fleece.