I don't use a 13ci tank but I want to say I saw some threads saying 150-200 depending on what kind of marker you are using and if you auto trigger a lot. Single shooting is a little more efficient. Check the stickies for vids and manuals to make sure all your setting are good, TF put a bunch very useful manuals and vids for teching your markers.
I had the same question with my s6 and Mel from CCM told me that that normal due to the oring at the top of the reg and it's ok to have it backed off that quarter turn or so. I just put mine where I like it and once I air it up the pressure holds it in place.