So many nay-sayers! All it takes is a large pocket book, (preferably inexaustable public funding)and a panel of experts to create a "natural enclosure". Ask your most local zoo! My opinion is it could be done, and with appropriate habitats for different species, BUT, it would be expensive and have to be large enough to provide room for the transition of habitats. You would also be adding LARGE amounts of risk to your pets. Predators, parasites, pathogens, and other microorganisms that you would have no control over. Your pets would also have no defense against them, (other than their shell) as they are not indigenous to your area. None the less, you "could do it". You would have to create a large sump either covered, or separated outside the perimeter of the enclosure. My first thought is a shallow stream, where a slow moving, (but enough flow to carry waste away) stream would drain into your sump area through a screen too small for your smallest pet to get through. (Maybe large holes cut into the side of a 55 gallon drum in a grid pattern.) That sump would need to be AT LEAST a 100 gallons, (not necessarily all in one container), and contain a prefilter, mechanical filter, and bio filter to treat your tortoise wastes. Since they would use it infrequently, (after all, they are tortoises)it would probably work fine to treat the water so long as it could get enough time to chemically breakdown, and balance. Your prefilter could be as simple as a mat of plant roots near the drain to the sump, or a settling chamber, which would also pre-treat the waste, while allowing the dirty water to flow through. Properly chosen, the plants would also provide a food source. You would pump from the sump, beyond all the filters, back up to the head of the stream area, and the water would carry wastes back to the sump through the drain system. Experimentation would be needed to set the water flow, then it would have to be adjusted as the plant growth varied. The automatic requirement is the most interesting part of your idea. THAT could get very expensive! Filter back washing to waste, chemical monitoring, water level, etc. is quite a design feat in itself! But if you are willing to monitor the water level, and run a hose a little every few days/weeks, it would not be too bad to have it manually operated. In fact the bigger the sump, and filters, the less attention it should need if designed right. A simple toilet valve could control water level for you, but the supporting infrastructure becomes an issue. Solar pumps are certainly available to move the amount of water you need to move, and most likely, move it often enough to keep the water healthy, depending on system loads. (size of pond exposed to sun, wind, and relative filter sizes, how many leaves get in, etc.) Just like your pets, water features need attention. So you know, there is no such thing as a maintenance free pond, just one that hasn't been maintained, or is not yet completely full of stuff. Nature puts things in, we take them out. We do this to keep the area a pond. In nature, the pond is always changing, and always filling with gunk, getting shallower and shallower all the time. What you proposed is certainly not a simple project. What other proposed is simpler and more practical. It certainly is cheaper, and less risky to use a large saucer, and unless you are willing to create a large water sump, a lot less headaches! You have easy control over the quality and quantity of the water in the saucer, and simple disinfection with a weak bleach solution provides a micro guard. When you decided to take on pets, you decided to devote a portion of your life to their care. If you want them to live in a natural area, you will need to return them to their native lands and set them free. Other than that, continue to care for them daily. They deserve your attention! And you benefit from providing for them. Heck, they're tortoises, you only have about 25-100 years to take care of them! Buck up! -TT

Thanks, Gilroy! I wonder if anyone has success posting images from their libraries directly to gardenweb? We've gone back and forth--from making the pond into a firepit--which would mean somehow making it drain snow melt and rainwater, to reviving the pond, which means a bigger financial and time committment, plus lots more to learn (just trying to figure out the GPH and the lift and the head height and immersible vs external and direct drives vs mag drives...! Yikes!) We've also talked about making it a firepit surrounded by a pond or somehow making it into a hot tub or outdoor pizza oven. It's the focal point of our backyard and letting it fill up with algae and Mosquitos and weeds every summer just isn't working. Our neighbor put in a swimming pool and all the noisy equipment sits atop the hill just above the pond's retaining wall and behind a hideous chain link fence. We're hoping to cover up the noise with the waterfall sounds and eventually put up our own wooden fence to hide the chain link. But, wow, what a lot of work and expense. I love old houses and am glad you're trying to stay true to the design of your home's era. Have you posted any photos of your home and where the pond is sited in relation to the house? Good luck!

Yes, I keep catching glimpses of this fish when I'm out feeding the fish twice a day or working on the pond but only brief glimpses. After further examination, I think he's at least 2 inches long. He seems to follow the "school" at least some of the time, swimming lower to the bottom and in the back of the pack. He's very hard to see because he totally blends in with the color of the algae-coated bottom and sides of the pond. He doesn't seem to have a long tail like my 2 comets or the shubbie which is why I was thinking maybe koi but I'm hoping goldfish. I guess I will have to be patient and wait for him to decide to be bold enough to try and feed with the others in order to get a better look at him. There may be others in there but I haven't seen any thus far. I have crystal clear water but plenty of water hyacinth and underwater hiding places so there are probably some more somewhere, unfortunately. My first fish were baby koi from a cull sale. They sold me way more than needed for my 1500-1700 gallon pond and I gave away all but three of the koi to a fellow ponder with a big pond several months ago. If I had it to do again, I would have stuck with goldfish for this pond. I absolutely love my goldfish, even more than the koi. They are tamer and don't wreak havoc on my anacharis like the koi.

Of course he won a ribbon, I expect nothing less from Harry! Love the bit about the clean water, how considerate of them to provide that!