Have not had any problems with pond for a good 10 or 12 years now. There is lots of big plants in my pond that do take big drinks, also the water evaorates quickly when we get those hot dry winds so then the pond gets topped off with fresh water. Being doing it this way for many years now. Sometimes I think people disturb there ponds way too much, and that really can get in the way of trying to balance the pond. Like I said before, used to use good bacteria and Shac Ponder, have not needed those products for years now.
My first couple years of ponding it, I had some trouble here and there, made the mistake of having too many floaters one year, long time ago, found that they can choke pond to death slowly, use sedges mostly now cause they clean better than any other plant in the pond, read that in National Geographic. Too many lillys can act like a blanket and smother and over heat pond too. Learned lots over the years. Learned trees and caterpilllers are real good for my pond too, some people just don't understand cause they don't have trees and caterpillers maybe, maybe they just did'nt study them for years like I did.
Nature gave us ponds and trees together, never seen a natural pond in nature with no trees. Many years ago when I was in my early twenty's, someone asked if I wanted their goldfish. It was getting late in the year and winter was coming soon, they said if I did'nt get the fish they would freeze to death. I went to get the fish, and could hardly find the pond because so many leaves had fallen. Then there under the tree was this little fish pond, no bigger than 50 Gallon, bottom of pond had a good ten inches of leaves, just laying there at the bottom. As I studied this little pond I was amazed, no pump, crystal clear but golden water, and big fat healthy goldfish. Never forgot that little pond.