I am a great fan of streams. I believe mine does all of my filtering. I don't actually know that spilling is helping but in any of your cases, all you could have is flowing as a mechanism for cleaning/filtering. Anyway, I don't have a specific solution for you, but I want to add to your thoughts. I suspect that the double piping may be your solution. It would be a 4 'bottom drain' connection! However, it seems to me that mixing method 2 with glue would give you what you are looking for. Admittedly, I have little faith in sealing liners either, but to the extent that you believe in plan 2, the glue would give a semi-seal and prevent movement that might make the weight theory succeed. I"M Still with plan 1. Thinking about plan 3: It seems to me that a single linear rubber clamp is just as good as the square or circle. neither one of us knows what that would be but it simplifies things a bit. I do have one goofy idea that you might think about and mix in. I wanted to suggest a clamp that didn't involve screws with MORE holes. My thought is to cut a slit lengthwise in some pvc pipe, wedge it open, and slip it over the sealed pieces of liner or rubber additions. Perhaps one could use more flexable roll tubing to curve up edges. That black underground tubing is very stiff and still give a spring clamping effect. I'm still with number 1. I suppose my plan would be different from yours only in calling that stream an Inlet not an outlet. I'd put a big pump in the big pond and pump the water to the far end of the stream that would then 'flow' back thru the stream and pipes.

I love the pictures of Emma! How did you get them inserted with a reasonable size rather than gargantuan like mine? Unfortunately, we've been dogless for two years. Because of the amount that I currently travel, it is probably going to be a couple more years before I can defend getting a pair of goldens again. BTW - I subscribe to the theory that goldens are much happier in pairs. Ours used to sit patiently under a big pine tree (where the large pond is now located) for hours after they chased a squirrel into it. What type of snail would work? I am not aware of any places locally where I can capture wild ones. Will the pet store variety work? Are frogs likely to stick around or will they go "on a walkabout"? Do I need to introduce plants before fish? Right now, the pond is pretty sterile. In a week or two, when the flowering trees drop their blossoms, some organic matter will inevitably end up on the bottom of the pond. BTW - we are at 1/4 mile from the nearest natural body of water. So, no need to be concerned about prison breaks by the pond critters.

In response to your first question concerning the pump. What you didn't mention is the performance of the pump at different head, i.e. how much water flow does it deliver at the highest point. You also need to calculate the head loss of the piping/plumbing you use. Most pumps (at least here in the states) include a chart showing the pumps capacity at various head levels. Also keep in mind that head is measured from the water surface and not ground level. Question 2. Koi and goldfish love a strong current in the pond as long as they have some little area they can go to rest. They will often be found playing in the strong currents from a waterfall or under water return. Question 3. Koi and goldfish are "coldwater" fish and will survive winters just fine as long as you keep a small hole in the ice and the water in the pond doesn't freeze solid. They may appears listless or dead in the spring but as the water warms they almost always come. I think your pond is deep enough that you won't have to worry, especially if you keep a tank heater (like the ones farmers use it stock tanks) in the pond in winter. 4: I would use goldfish and not too many. Koi will get big and make a lot more waste than the goldfish. Oh, and don't use the "fancy" goldfish as they are not as hardy as the regular ones. 5: You can go either way on this one. Some people I know turn their pumps off other (like me) keep them running year round. The main issue is to keep enough oxygen in the water for the fish. In any event with your winters I would put in a waterfall bypass and return the water directly to the pond and not use the waterfall during the winter. Running water in the waterfall during the winter is a request for disaster. The water will gradually freeze and often will cause the water to escape the confines of the normal water column resulting in a drained pond and lost fish. 6: Just keep the pump running to keep the water oxygenated. 7: I am not an advocate of putting gravel in the bottom of a pond. It is a recipe for disaster if you have fish. All the fish waste gets in and under the gravel and it is very hard to keep it clean. This results in a layer of nasty bacteria beneath the gravel which will eventually be harmful, even fatal, to your fish. A gravel less bottom makes cleanup easy There are a lot of aquatic plants that will grow in your environment. you can use marginals and set them on the "steps" and maybe one hardy water lily in the deep or next step up. Floating plants do will in a pond as well. Of course this all depends on how much sun the pond will get. DO NOT use any "potting soil" in the pond. You can plant most plants in pea gravel and they will do fine. Some people use regular old clay soil with nothing added but I find that the fish like to dig in it and then it gets all over the place and the plants end up floating out of the pots. I'm sure you will get lots of good advise from the users of this forum. everyone here is very helpful and knowledgeable. Best wishes on your journey into ponding.

lesliew I have a pond that is about the same size as yours. I have a gravity filter that keeps my pond clear all year round. This filter is outside of the pond and it looks like a large utility tub. I have it sitting right next to my pond so I put a small fence in front of it to cover the front of it. This is how my system is set up: my water comes in from a garden size hose into a tube that is about 5 in diamiter ( I have a rock that holds the hose in place). The water then falls into the very bottom of the filter in comes up through a small grate,furnace filter, lava rock in bags, then roots of iris, water celery, anacharis, horn wort and out a 3 in tube that feeds back into the pond. I have a bottom drain that allows me to clean this filter out every spring. When I clean it in the spring I take out all the iris, chop them to pieces and give to any fellow ponder that will take them, hang on to a clump about 6 in in diamiter. throw away all water celery, it comes back anyway, replace lava rock. I buy the landscaping type just make sure you rinse them throughally before you put them in. Buy a new furnace filter at hd they are about 5.00 and worth every penny. The grate sits up about 4-5 in off the bottom so that allows all the fish poop and rotted stuff to settle in that area. When you go to clean out the filter you will want to save this sludge...it is black gold, my plants love it in the spring its like a energy drink for them. Once you put it back together you are done until next year. I do have to clean my pump about every 4-5 weeks but that is easy and takes about 10 min. I have pictures of my filter all taken apart that I can mail to you, they were not done on a dig camera, just let me know.