Sharon, If your peg tube is one of the types that has a "whip" end (extends away from the body) you should be using a rubber band on it. Fold the thing in half, and then in half again, and put a rubber band around the bundle. The kink nearest your body will prevent Anything from coming through it, and the bundle of tubing is a bit easier to tape down.
At one point, when I was still using whip type peg tubes, I slid a paper clip over the tube near my body to pinch it shut. I wore a simple string lanyard around my neck, that hung low enough to hold onto the top of the tube and keep in vertical under my shirt.
Get creative with pinching the tube shut. Tiny clothes pin, paper clip, bobby pin, crimped and rubber banded, crimped and tied with a shoe string. Make certain your clamp pinches tight enough to completely close the tube, but not so tight that it cuts into the tubing.
Only docs who have never worn a peg tube continue to install tubes with whips. The real pros install the MicKey type tubes that are flat on your stomach and have no whip. The head of the peg has a valve and fitting. A whip with a special end is inserted and twisted into the peg when feeding, and then removed. No tubing, no leakage - very nice. Some of us live by our pegs and have learned many of the lessons the hard way. Be strong. Tom J