Get a new colon hydrotherapist. If you are working wth a decent experienced hydrotherapist there should be no need to empty on your own. She may be filling you too much, too soon. A trained tech uses pressure gage feed back and can tell (along with your feedback) how much water to be using each time (especialy on the first fills). Stay with a closed sytem when.
I prefer a gravity system and make sure that filtration on the unit is top notch and includes a uv filter.