So i started digging my pond and I have another question. I have noticed from just eyeing the pond, it looks to slant maybe 6 inches or less. Now would I still need to build a dam on the sloping side? Or how much of a slope would it need in order to build a dam?
With 0ne side of the pond being 6/7 inches higher than the other side of pond,would I need to build a dam?or could I try to level everything out?
This will be an all natural pond with no liner.45x25 ft pond.

That's going to be a nice sized pond. You can build the low end up so the pond is more ground level or you could do something fun on the high end using rocks and/or vegetation.

If you slope that high end so it gradually goes down, it would not be noticed and could be a great place to put plants that like a little more water. Or leave it as a 'cliff' and put some rocks in there for affect.

If you want your pond to have a level edge all the way around, build up that low end. You need only a fracton of an inch for the water to flow out the low end (and, depending upon how much digging you want to do) a deeper pond.

Can you explain more or draw something to show me what you mean on sloping the high end?Thanks

When you say build up the low end does that mean a dam.can really put a dam cause there is a big tree by the low end.do mean just add some dirt to build up and tamp it down and tight?when you say slope the high end,can you explain to me how to do this

I suggest a laser light and stakes to level the water line for the pond- so rain doesnt cut itself an overflow and erode your pond away. Do not forget to provide overflo access.
Simple dirt build up and tamped to create the level water line works only when the width of the base of the dyke is 3or 4 times the height. Even when tamped is still soft, so can erode easily. My overflo is a liner that protects the earth at that point. I do have to be sparing of rocks as snakes are drawn to the water.