29 replies to this topic

[mjz3348]

I installed a new 10,000 gallon pond with stream system that acts as my bio-filter.
The water is excellent quality as a result - and the koi/goldfish are thriving (fat, big and happy).

But - the water is quite green (even though in winter). I thought the stream (with lots of water plants along the bank) would suck out the nutrients from the water and prevent the single celled algae from growing to dense - but not to be.

I am thinking of installing a UV light system to kill the algae and get clear water.

Can anyone suggest a UV light sufficient for this size pond? I'll post pics when I get a chance.

[DrCase]

Is there any way to clean your stream bio filter ?
And are your plants growing now ?
Last ? were is your pond located ?

[koikeepr]

oh, it all depends on the UV unit you are using. Some will say that a 30 watt UV bulb will work, others will quote a 52 watt one will work. Heck, I've even see 200 watt ones for a 10,000 gallon pond.

Research the brands and see which one will be most cost effective for you. With a pond that size these UV sterilizers can be pricey, and wait until you see the cost of the replacement bulbs. Yowza!

[koiguy1969]

a u.v lights ability to destroy algea depends alot on the rate of water flowing thru it. the higher the wattage the higher the rate of water flow that can be efficiently exposed.
do you plan on implimenting it into thre present plumbing or running it independantly with its own pump?

[mjz3348]

DrCase said:

Is there any way to clean your stream bio filter ?
And are your plants growing now ?
Last ? were is your pond located ?

Pond is located in Houston - we just went through a bad freeze - brought the water temperature down to 40 degrees...but now the water is at 68. I just fed the Koi for the first time in about a month.

[DrCase]

I was thinking if the exes nutrients left in the stream, were causing your green water.
maybe if you could clean the stream out, you woudnt have the problem

[mjz3348]

Stream is clean - and full of plants. I would expect the plants to remove most nutrients from the water.

[DrCase]

mjz
Can you put up a few pics of the pond and stream for us ?

[mjz3348]

DrCase said:

mjz
Can you put up a few pics of the pond and stream for us ?

Will do ... need to upload them so they can be viewed easily ...

[mjz3348]

DrCase said:

mjz
Can you put up a few pics of the pond and stream for us ?

Here you go:
http://i57.photobuck...48/IMG_0897.jpg

You can see the stream on the left and the pond is in the top of the picture - green water.

The pond is exactly the same as the pool - same construction and materials. The pool is chlorinated and of course the pond isn't - that's the only difference. If I could get the pond clear - it would look like the pool - except you would see fish. The pond is 4 feet deep and has rocks to provide perches for the lilies.

There are two pumps systems on the pond. One runs the stream. Water is pumped from the bottom of the pond to the head waters of the stream and gravity drains the stream water back to the pond (1 foot drop). The second pump operates the skimmer and water feature in the pond (mini -water fall) and has a cartridge filter on it. The cartridge filter is useless. It is off most of the time - but may be used to connect the UV system I am thinking of installing. I need a much better filter design to go with the stream.

The stream does the trick for bio-filtration. The water quality in the pond is excellent - just green.

There is also two overflow systems for rain water. Rain water will flow into the stream and provide natural turnover of the pond. I have seen nitrates reduced to near zero after a big rain event.

And I have seen some of my smaller goldfish swim upstream like salmon. Very cool.

[koiguy1969]

if you dont have at least a mechanical filter to catch the solid waste so it can be removed from the system it just keeps building up and bio-degrading and putting nitrites and nitrates into the water and feeding the algea.. ideally your filter should be a flushable one. if your were to add one of our barrel, or stocktank filters before your stream and flushed it once a week or two you would be amazed at what you see come out; the poop soup, and sludge that in your case is being left in your pond and stream. this is whats feeding that green water. theres a few different designs in the DIY section for 55 gallon barrels and a 70 gallon stocktank design also.

[DrCase]

Nice place you have down there
I really couldn't see the stream , But like Koiguy said that steam is your problem
The stream will help you , But if you can add a filter at your head water be for the stream that is flush able, you will have a clear water

[mjz3348]

DrCase said:

Nice place you have down there
I really couldn't see the stream , But like Koiguy said that steam is your problem
The stream will help you , But if you can add a filter at your head water be for the stream that is flush able, you will have a clear water

Zoom in on the picture and you will see the stream. It's to the left of the pool. It starts at the bottom left of the picture (head water) and flows along side the left side of the pool and then disappears under the waterfall/rock. It re-emerges on the other side and flows to the pond.

Can you recommend an appropriate filter for the pond? (10,000 gallons).

[koiguy1969]

are you looking to buy or build your filter?

[mjz3348]

koiguy1969 said:

are you looking to buy or build your filter?

Either way. I do have a pump and plumbing already connected and working. I need to put a "filter" in the loop with backwash capability. The filter that is there now is a "spa" Hayward cartridge filter. Absolutely useless.

This is what happens when you let a pool designer/builder tell you that he knows how to build ponds. He didn't know jack -)_$#439r58. And it showed. I didn't pay enough attention - which can happen when you are building a major house with a lot of other things vying for attention.