esshup is correct.

I should have written more clearly. In my estimation - the amount of cover and structure that active planners on Pond Boss put into their ponds is higher than the large reservoirs.

I was thinking of the great threads I have read on PB and how much more structure the posters added to their already impressive initial plans - after getting additional feedback from the forum.

esshup actually works with pond owners of all shapes and sizes, so his view is MUCH broader than mine!

However, that wasn't my main point. I would imagine that active pond managers continually adding items over the life of the pond should provide benefits relative to a large reservoir, that probably only has a few additions over the course of its life.

I would think(?) the carrying capacity of the large reservoirs should not change over time - in theory. However, in practice - the carrying capacity does change as the natural cover (that supports forage species) diminishes over time.