Bottom line is, a pond is a pond is a pond is a pond. Incorporate the right amount of fish, plants and water movement, and there is essentially NO difference between a million gallon lake and a thousand gallon pond. Believe it or not, Whittstock's pond is built no differently than your 1000 gallon pond. Still has liner (different type), gravel, rock and fish. I've been building ponds for the past 17 years now and have seen everything from the little fiberglass tubs with a fountain all the way to the hideous bio-filters and UV sterilizers made from garbage cans, and now the AquaScape Designs system. I can tell you hands down that there is truly no better quality pond system than AD, and if you know of one then please show me... or if you don't know of a better one, then walk the walk and build us a better one. Greg Whittstock knows exactly what he is talking about; however, I will agree that AD (as many smart manufacturers do) sells many useless "fluff" items that are really designed to make the manufacturer more money and nothing more. These "bells and whistles" don't necessarily make a better end product. Regarding annual cleanouts: AD simply recommends marketing annual pond cleanouts to your past customers as a way to maintain contact and obtain maintenance income. Is it truly necessary? Absolutely not. I installed a 5,000 gallon pond in my parents front yard some 6 years ago. Guess how many times its been drained and cleaned? NONE! Guess how nasty the water is. It gets clearer every year! How many times have you caught Mother Nature pressure washing her ponds? Gravel: I can only imagine the construction of someone's pond that isn't using gravel. OY-so much to learn! I must say that if you cannot realize the ingenius of such a simple and effective system, then you must be doing something wrong. Gravel is an essential component of ANY healthy ecosystem and anyone suggesting otherwise should NOT be building ponds, but rather installing swimming pools. Think about this: when was the last time you saw an aquarium without gravel? Ever notice how much crud accumulates in such a quick amount of time without it? Your pond is no different. Trust those of us that know and ignore the nay-sayers that don't. Gravel is your friend. If you are getting large amounts of leaves and muck in the bottom of your watergarden as you described, then you obviously have A) too many trees B) too small of a skimmer C) both. Regarding the comment about AD systems being for low levels of goldfish only, not KOI: I just have to say-TRY AGAIN! If that were the case, then why does EVERY SINGLE pond built by AD have KOI? And being that they DO have KOI... why is the water quality extremely clear? Answer: because AD is designed for both goldfish AND koi. The key is not to overstock the pond and certainly don't overfeed the fish. More fish = not better. More feeding doesn't make your fish bigger. They don't process food like we do. Regarding BioFalls Filter Mat Cleaning: If you feel the need to do this, then get a large washtub and bail some pond water into it. Take the filter mat out of the BioFall and rinse it around the washtub until it releases most of the grainy muck. This will enable your bacteria to survive while getting rid of the foreign matter that slows down waterflow. In closing: remember that a pond is just that. Ponds have leaves, and to an extent... a certain amount of "muck". If you are looking for the squeaky-clean pond system, they call this a swimming pool. Add chlorine, get a pool cover and go to bed. Good night!