Want to make my pond more shallow

[ItsBoTime]

I’ve had my pond for about 3 years. I wish I could start over and make it have less depth though. It can be a lot to clean up due to the amount foliage during fall and spring. I got a ton of muck last year and realized small pebbles were an awful idea to put at the bottom, it took me days to clean. I do see a lot of people mention pea pebbles though, I don’t know if I should do a certain one, I am kind of at a loss on knowledge. I removed them all and have big rocks and I have a lot of drift wood. I wish I would have just done normal liner I instead bought a 145 gallon polyethylene liner. Something I want to do though is make my pond have less depth. I feel I can make it look nicer this way, maybe line it will stone or something. Any suggestions of ways to make your pond more shallow, obviously less water but you know what I mean. Here is some pictures. Also, would like to know what others put at the bottom of their pond that works well.

*promise it doesn’t look so dirty all the time. Birds been perching like crazy which I love and been gone for two weeks*

Thank you!

80-in L x 54-in W Black High Density Polyethylene Pond Liner (145-Gallon)