buy some whatman fast caps! I just filtered 332 mls of 300mg/ml test E in 5 minutes, NO SHIT! I have a vacuum pump that keeps a steady 25 in/hg pressure, I have never seen gear filter so fast, temp was about 65* C, I have had the filters for a while, this was just the first time I've used on. They say that the filter has a life of 10 L, thats a lotta gear for one filter membrane! They're not cheap, I think they're about 25-30$ a pop, but so worth it!