Cannot get rid of green algae

[Relic]

Many years ago (decades) the Fort Worth Zoo had an aquarium inside the grounds, and immediately adjacent to the entrance door, on both sides, were two small pools of large koi - small as in 2-3 feet deep and perhaps 2-3 feet wide and 10-12 feet long (rectangular). And they were brim FULL of fish. Jammed with fish! No plants, just crystal-clear, flowing water that must have run through a filter the size of the Space Shuttle...

 

[Lisak1]

Many years ago (decades) the Fort Worth Zoo had an aquarium inside the grounds, and immediately adjacent to the entrance door, on both sides, were two small pools of large koi - small as in 2-3 feet deep and perhaps 2-3 feet wide and 10-12 feet long (rectangular). And they were brim FULL of fish. Jammed with fish! No plants, just crystal-clear, flowing water that must have run through a filter the size of the Space Shuttle...

We visited a public garden that had an indoor growing space with a "stream" running through it. Less than a foot deep and teeming with big koi. It was really beautiful and well done, with a number of small waterfalls and pooling areas, but I was worried about the big fish. We asked and they said the filtration was massive and the volume of water was much larger than we guessed. They also said they used the water from the fish to water the plants in the arboretum - and they were lush and beautiful!

 

[Giovanni]

Hi
1000 gallon pond, steep sides, no plants, 5 Koi, all test readings low except for PH (8.5). The pond is about 15 years old. In the last five years I have failed to maintain a clear, algae-free pond for longer than a couple of weeks. Oasis green2clean 24000 combined filter and UV (25watt) with an Oase Aquamax 8000 (litres per hour). I have tried a whole range of products and processes to try to clear the green but nothing lasts more than a week or so. I have completely replaced all the filter pads (I had an infestation of worms in the old set and wondered. Whether this was causing part of the problem). The garden is south facing and the pond gets direct sun for most of the day.

I have two questions...

Short term - can anyone suggest any products or processes that might clear my pond?

Long term - Next year I am looking to redesign the water feature and could change the filtration system for a new one at the same time. Recommendations, please, for what I should consider purchasing? I live in South Wales, UK.

Many thanks

Chris

Hello, Green water is a bummer, but you are in luck. Your pond design is not a Formal design (sharp rectangular angles); it is more on the naturalistic side of things soooooo, take a bamboo pole or something and section off about a 3rd of your pond and throw in some floating water plants that will quickly spread and cover the surface of that area of your pond; Parrots feather, Water Hyacinth, Water Lettuce, etc. You have too much nutrients in the water (uneaten food, fish waste, etc; and it is getting too much SUNLIGHT.

 

[mgmine]

As has been said you have too many fish. For me, any small to medium size pond with more than three or four fish is too many. Maybe not for the health of the pond but for the serenity of it. But your problem can be taken care of with a second UV light as you suggested. Get a good one and change the bulb every year. Within a week you should have a clear pond.

 

[GBBUDD]

Many years ago (decades) the Fort Worth Zoo had an aquarium inside the grounds, and immediately adjacent to the entrance door, on both sides, were two small pools of large koi - small as in 2-3 feet deep and perhaps 2-3 feet wide and 10-12 feet long (rectangular). And they were brim FULL of fish. Jammed with fish! No plants, just crystal-clear, flowing water that must have run through a filter the size of the Space Shuttle...

You don't want to try and duplicte zoos or aquariums it will cost you a arm and a leg not to mention a ton of time.

 

[Lisak1]

I think that's the secret in many of these commercial display ponds - lots of filtration that you can't see and wouldn't want to look at in your own yard!

 

[GBBUDD]

in the four years i have been ponding i have seen thousands of questions and posts but only one has ever said that the bog failed them.

 

[Lisak1]

but only one has ever said that the bog failed them.

And didn't we have many questions about how that bog was built? I seem to remember it was real sketchy.

 

[GBBUDD]

Yip it was,

 

[GBBUDD]

With all the versions of bogs out there it was just the one that someone came on here ranting bogs were no good and he was going back to a Skippy filter. I say I wish yeah luck. All I know is is that my bog is not the average it is not as aquascape intended but its the same principles. And I have been very happy with the efforts to build it.

 

[CometKeith]

Hmmm.. this is an old thread but a common problem! I wonder what happened to the original poster’s fish!

 

[Kurtkoinut]

My pond is just over 2 years old. I did not have the pleasure of the spring with this pond last year. This year I knew I had too much algae. I built a bog-ish pool that I pump around 2000 gph through. The inlet is under a foot of lava rocks. The lava rocks have various water plants growing in them. The water returns to the pond via gravity, out the top of the bog pool. A little over a week running, and my water is clear. I still have a little string algae here and there, but the fish seem to eat on it, so I'm not worried.

I think my pond is a testament to nature doing its thing. I have no special equipment, and I have not used any additives at all. Even with only about 40% of the water being shaded, i have nice clear water. My bog might not be a textbook example, but it's working excellent so far.