is it bad for my tire (KH 20in trials) not to be aired up all the way? I finally got to where I can jump about a foot and I was ridin in a ravine jumpin down the side of it and my tire started letin out air and so I aired it up and it feels like I’m goin to have to relearn to jump 
Your tire only needs enough air to keep the rim from bottoming out when you jump. Exactly how much that is depends on what you’re riding and how much you weigh.
do you run it tubeless ? a inner tube will not let air out unless it has been punctured
if you do run tubless on your trials ( which i wouldnt ) its just one of those things, if you run tubless and do a lot of side hops the tyre tends to fold and let air burp out just keep a pump handy if this is the case or do it properly and buy a innertube 