Harm Reduction Whatman Micron Filters

After following mega thread for micron filters and strapped on a micron filter, I came across something I didn't think would happen, it was hard as hell to pass the water through the filter. I imagined there would be pressure but I literally could not force any out when I used 1cc of water (I was prepping a single shot). I got maybe 3, 4 drops outs before it wouldn't really go through until I loosened the cap up just enough and my 2mg solution of hydromorphone leaked out >.<. I then tried just shooting water through it to get a feel for it and it seems I need alot of solution to make the filter work all.

My question is, does anyone have any advice on how to prep 1cc with these filters? I feel as if alot of the water is lost when pushing through only alittle bit of water. I'm also trying not to waste the filters or the pills :/

what kind of micron filters are they? what membrane and thickness?

I think the most common are 0.2 micron PVDF.

Yes, they are .2 PVDF filters.

try running just water though after you run your shot though to get most of the drug out