Leveecius

For about a week now I've been e-mailing TT directly and not getting any answers, and they never answer the phone and don't do callbacks, so here is what I'm left to do. I am trying to finish my new build, but am just trying to get a couple of questions answered before purchasing. I was looking at the P22-D5 pump/reservoir setup for my cooling needs, however, I'm wonding if the reservoirs are interchangeable? I'm trying to run a 500ml or 600ml reservoir in my setup, but the one it comes with is not that size, but they won't tell me if I can just replace the reservoir or if I need to go with a separate reservoir and pump setup. Anyone have any input on this?