dang it....I had a really well though out response all done, and my internet explorer crashed. So I'll try again...lol!! First...a few comments regarding how koi ponds compare to aquariums. Normally, aquariums are lightly stocked with small fish. It's really easy to keep the ammonia/nitrite/nitrate cycle operating perfectly in a correctly stocked environment. Same as a rock bottom pond...lightly stocked and properly maintanied it can work. In a pond's bio filter, ammonia is converted to nitrite and then to nitrate. Nitrate is most easily removed froma koi pond by way of regular water changes. Ever try to keep an aquarium with goldfish? Many goldie keepers I know keep no gravel in the tank at all, because of maintenance. That gravel gets really filthy very fast. I had a lovely goldie tank once....and gave it up. the maintenance was a nightmare! I'd rather deal with a huge koi pond any day of the week. Some people are reporting sucess with rock bottom ponds and no maintenance. Again...it is directly related to stocking levels. I hope these ponds continue to perform well for years to come, but for the vast majority of people, they will not. Most watergardeners install their ponds (and rocks) and then run out and buy a bunch of adorable little 5" long koi. The koi grow.....fast. They produce mountains of fish waste, which all gets trapped in the rocks. But because the pond looks clean, the owner is lulled into a false sense of security and does not think that there is a thing wrong, until the fish start dying or the fins start rotting off. Then they do one of two thing....they learn where they went wrong and correct their mistakes, or they just buy new fish (which is unfortunatly what most people do). Matt...you are on the right track with your new pond. You certainly can install your bottom drain now and add the rest of the system later. But instead of using a pipe cap, install a 4" ball valve on the end of the line. The water can't be permitted to sit stagnant in the unused drain line for too long or it will start developing the dreaded hydrogen sulphide gas. Opening that valve every couple of weeks and allowing the water to flow out for a couple of minutes will prevent the problems. I am attaching a link to the Atlanta Koi Club's web site. They have an excellent pdf that explains a lot about how a koi pond works, water quality, stocking levels, how much biofiltration is needed and many other wonderful facts. Cindy

Back years ago, I think in this forum, several members were interested in building vacuums specific to cleaning fish ponds. I was one who got into it. I developed several vacuums and went to several people's ponds to test vacuums in different conditions. Here's my page on vacuums. There's also links to building vacuums. I don't know your pond, but in general, some species of string algae when alive and mature is like horse hair. Bind a little together and it's like rope. I've pulled every bit of out of a pond in one pull and it brought pretty much everything in the pond with it up to the size of a brick. I don't think it would be possible to remove the string algae without removing the hornwort too. Once removed you could try and get some hornwort out of the string algae and replant. But string algae can come back, although often it's another species or it doesn't grow the same way next time. Even if you had no hornwort, gravel or reeds, I don't know of a single vacuum that is effective with string algae. If the string algae is still alive it is basically one plant and in your size pond when removed it could be in the 100-200 pound range. No vacuum can't handle that. I've seen a vacuum with a cutter on the end that's suppose to be able to cut the string algae. I doubt it works, but you should read reviews if considered. Even dead string algae, which breaks up easily is a big problem for a vacuum because of the volume. Easier to remove by hand or a swimming pool leaf rake. For live string algae I used 2 pieces of 1"x1" wood nailed or bolted together in the middle so they would open and close like scissors. I'd make them about 5' long. Open them a bit, push into the algae, close, and then spin them so the algae wrapped around the wood. Once I had a good ball I'd pull it out. Generally every bit of algae came along with this ball, along with anything it was attached to. Different species of string algae and the different life cycle stages can require different methods. I learned 2 basic things. First, there is no single vacuum that is effective. Ponds are cleaned in steps, removing big stuff first and ending with the small stuff. Different tools for each. Second, don't build a pond that's hard to clean. Loose rock, gravel, plants, all good great...until it's time to clean. I mortared rock so it was easy to clean and moved all plants into their own beds and so their crowns were above the water. Crowns above the water = no string algae = happy pond keeper. That means no underwater plants like hornwort and no lilies. Lilies can get their own pond or their own deep water bed adjacent to the pond so the pads can grow out over the fish pond.

Filtration,filtration,filtration , sounds like your biofilter isn,t handling the waste output of your fish , is your pond clean " no sludge" or rotting vegetation ? this adds to the toxicity of the water , i believe the formula is 1 inch of fish for every 1 cubic foot of pond surface . example: if you have a 10x10 pond you have 100 cubic foot of pond surface , thats equivalant to 10- 10inch fish provided you have adequate filtration . and i go by half the recommendation of the manufacturer , if they say your filter is good for 1000 gals. i would subtract that by half if you have fish in the water

That is a small area, so it shouldn't cost much. The current 'stone' appears to be the standard stuff that Lowes/Home-Depot sells. It isn't expensive. This is something that can be done by hand. I had a stone patio put in by the local semi-experts. It was large enough to require a big truck, but you could get needed stuff in a pickup or a van from a landscape center. If I'm not mistaken, we leveled the land, added an inch or two of gravel and dumped sand on top. I think that they may have had a mechanical vibrating tamper, but for such a small area, you could just use a manual tamper. It is just a heavy flat bottomed piece attached to a handle. Since it is in sand, even if it sinks a little, you could always just remove the bricks, add some more sand and you should be set. Of course, you could always go lazy, and throw some dirt in there and plant some flowers.