My pond water has almost always been clear except that both the pond and stream have often had a heavy load of string algae. In my second year I added 3 goldfish mainly to see movement deep in the pond to check for clarity.

I originally added pieces of one bunch of watercress from the produce section under rocks in various sections of the stream. They all grew and survived the winters and produced large root systems. I found that these (and other plant) roots would trap the fine crud circulating from pond and stream. On occasion I would yank out excess growth, and gobs of crud would be removed with it. Admittedly this also stirred up more crud but it was almost immediately removed by other roots and perhaps the filter. The actual cress and fallen leaves etc. would catch the algae that I would grab out with my hands. I recently had the sense to use a toilet brush.

I have recently had a dramatic decrease in algae, especially in the pond where it had been collecting on an impressive growth of underwater pond plants making them look like green/brown cotton candy. Unfortunately, I have recently made several changes so the source of improvement is unclear. First, it is a new spring. I had also removed half of the pond plant algae tangle. I had been out of fish food and the fish had been subsisting on algae and snail eggs, frog eggs or whatever but that stuff seemed to be declining so perhaps the fish were focusing on algae, and most interestingly to me, I suspected my mini-me was leaking and I first diverted flow away for a week (indicating a 10gal loss/week and a larger nearby waterfall spillage loss), then pulled it out, removed the sponges which were clean with no crud or stinky smell in the bottom, eventually sealing the leak and reset the filter after at least two weeks of no filter. Soon thereafter, the algae almost disappeared so that for the first time in two years, the underwater plants looked like they were in an aquarium.

I suspect that the long stream with plants is my major filtering agent. I was surprised that the mini-me seemed to be completely clean. I am pleased that my water has always been clear and that my fish, frogs, tadpoles, snails and lilies are (and always were) apparently healthy. I highly recommend a stream. I would be interested in any thoughts about the sudden algae decrease.

The stream has several small waterfalls in it. I installed a 3" pipe under each waterfall area, and capped each pipe with a black rubber fernco cap. Then at the end of the stream, I installed a 3" pipe that ran underground to behind my ponds, so I could flush the stream and drain the waste away. That pipe has a cap on it as well. So now all I have to do is remove 4 rubber caps and wash all the gunk away! None of the gunk flows into the pool at the bottom of the stream anymore. Cleaning the stream used to be job that I dreaded, and now I don't. It's very easy and fast and because it is kept clean, it can do a better job with filtration.

Your whole stream bed is an oxygenating bio-filter, as is the sides of the pond, where the short fuzzy algae clings to it.
There is nothing better than natural filtration.
"Horton"

Lisa

Horton, I was hoping you would say something like your response.

goodkarma et. al. I would love to show pics. One of these days I will learn to set up a Fliker or whatever account. I see your point about water addition/nutrients. I am on a well but I also have an extra pond that I call my resevette that collects roof and french drain runoff instead of using rain barrels. It is mainly for irrigation but I often top off with the resevette water. It sometimes has suspended mud etc. Although it looks tolerable coming out of the hose, it looks pretty brown sitting in the resevette. It doesn't seem to even temporarily cloud up the pond which again says good things about the stream where I add the topoff water. But it sure could add extra nutrients and while I was diagnosing I didn't need as much water and I think I was mainly using the well anyway.

ccoombs, I like your cleaning design. Im lazy and haven't tried to clean the pond bottom. I have blasted hose water or even the power washer into the stream to clean that and again it cleans up in 15 minutes or so.