One of my in-ground water gardens is only 50 gallons. I've had it for about 20+ years. It has a small pump in it to keep it aerated. I've been noticing that the water goes down several inches over several months. I know we've been dry off and on, but now I'm thinking that there's a leak. It's one of those black vinyl/rubber-type containers. It's unfortunately next to a big tree. Is it possible that a tree root has poked it? thanks.