Yes you can, I have been using a Can Filter 33 plus 6 inch inline fan setup for years and it works fantastically. Ive pushed and pulled air through the filter, and while they recommend pulling air through, I have not had any complaints either way. However, a big downside to pulling air through the filter is that you must make sure that every seal between the filter and fan is completely air tight because if not, negative pressure will suck air into the seal thereby bypassing the filter. If your setup is better suited to having air pushed through the filter, you should be perfectly fine.