How To Clear Black Pond Water

Hi all! Any ideas what would cause tea colored water to turn black? I put activated carbon in my waterfall to rid the pond of the tea color and now it's black! I rinsed the carbon until the water ran clear and placed it in a mesh bag. I test the water weekly. Today ammonia and nitrite tested 0. Phosphate tested 0.5 and PH tested 7.5. Could it be algea? I have some clear tubing circulating the water and there appears to be some black spots on the inside of it. Any suggestions on clearing this up would be great. PS. 2000 gallon pond, 4000 gph pump,4000 gph tetra UV bio filter, and 10 small fish.

sissy

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What kind of carbon was it ,I use activated carbon and it never turned my water black .The black in the tubing could be just some good muck .Water needs to go through uv slow to be effective .I just use quilt batting in a basket .
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I used Pond Logic activated carbon. Would the quilt batting work in the waterfall or better in the skimmer?

Can you take a picture? Is it the water that's black, or just what you're seeing in the tubing?

Fill a quart jar with water and see if it will settle out. Can you see particles in the jar. If it does settle pour off the water and let it dry. You might be able to tell the diff between pond sludge and carbon.

sissy

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Quilt batting will work wherever you get a flow of water but it will clog fast .So it does have to be watched .I keep a basket in my filters all the time with the reusable furnace filter on top to catch the larger stuff so the quilt batting does not clog as fast .When I was rebuilding the water fall I just used the quilt batting at first to
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pick up the disturbed stuff fast .

It has always amazed me how water that is clear in a jar can look so much worse when you have a few feet of it to look through.

Are you using any chemicals in the pond that might have reacted with the carbon ? (grasping at straws here)

The most plausible explanation is that you missed some to the fines when you rinsed the carbon. I am quite sure you will tell us you did not so maybe the sold you some dud carbon? Get some quilt batting and see if it will filter the stuff out. If not the I expect a water change is in order.

sissy

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salt will break down carbon and so will iron in your water .Here we have iron in our well water

Dave 54

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Could it be being caused by the tanning released by rotting leaves in the bottom of your pond ?
If it is I would suggest getting them out by cleaning the pond .
The only other time Ive seen black water was in the rivers of the Penines hear in the UK caused by peat in the water
We always wash through activated carbon and put it in boiling water to activate it then wash it through numerous times before using it could that be you problem you hvent washed it through propperly ?

rgds

Dave

Since removing the carbon the water has begun to clear. This leads me to believe that I either didn't wash the carbon out enough and/ or iron in the water as sissy said. Will try the quilt batting. Would also like to try natural zeolite. Has anyone had success using it to clear water? THANKS GUYS AND GALS!!

sissy

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zeolite I use in my filters and if anyone has horses they know PDZ horse stall refresher and I use dollar store bags.At tractor supply also
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I went ahead and bought some nu-foam at the local fabric store. It's 3 inches thick. Cut it to fit my spillway and put another piece in the skimmer. Water clarity has greatly improved since removing the carbon and using the foam. Did what Dave54 suggested and boiled the carbon and rinsed it thoroughly. Even after all that and soaking it in a 5 gallon bucket for two days, if I agitate it the water turns black. I'm going to contact the company to see what they say. Everyone have a happy Memorial Day!!