: What is the difference between a toilet that has a reverse trap and one that features Siphonic flushing action. I am putting a bath in my basement and I see these two advertised.Larry, For information on toilets, check out the review that Consumer Reports did on Toilets, 2/95 http://www.terrylove.com/crtoilet.htmAlmost all recent toilets use siphon action to clear the bowl. You can start the same action by pouring water from a bucket into the bowl. The water dumped into the bowl will start the siphon action that drains the bowl. This is why the fill tube in the toilet keeps filling after the flush action. Water needs to be replaced in the bowl after the siphon takes place.Regards, Terry