Question
-I don't think it is dirt. The is only one are higher than the pond  and there is no runoff from that. The water is almost like weak tea. I am using field stone bought from the nursery, and using that as a shelf liner, and Delaware River Stone 4-8"" on the bottom. I have hardwood mulch around the area. Also one more ?, should I have included a bottom drain?. I have 2 pumps(1 for each waterfall), Like I said all of my water hyacinth have died. The pond that i got these from still have there hyacinth.

Could the fish food(Tetra flakes be causing it?)  Hope this helps. I can e-mail you some pictures if that would help.

Thanks in advance
Rob
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-----Question-----
I have a 900 gal pond that is 6 months old. I live in Maryland. I have 2 waterfalls, one with a bio filter.I also have 6 goldfish. My problem is the water is not clear (and never has). It has a reddish brown color to it. Almost like a "red tide". I had about 20 or so clumps of hyacinths, and other plants. I even did weekly water changes. I and it would go back to murky brown within a week. Any suggestions?
-----Answer-----
Could dirt be running into the pond?  What kind of rocks, dirt, mulch, etc. do you have in and around the pond?  Algae are only rarely brownish.  Nothing is popping into my mind right now (I'm tired) but with more information, I may have more information.  For dirt in the water, you need to prevent more dirt from getting in by diverting rain from washing it in.  Coagulants like AccuClear and filters can remove dirt.  I'm not sure if you have dirt or something else.  Sorry to ramble (happens when I'm exhausted).  Good luck!

Robyn
fishpondinfo.com

Answer
Tea colors usually comes from leaves and branches.  If your mulch is leaching into the pond, that could account for it.  That will usually clear up as the mulch ages (it no longer leaches then).  Stone, if not washed, may make the water white cloudy but usually not tanin (tea) brown.  I don't have a bottom drain but many others swear by them.  They suck up small animals and leaves so they wouldn't work for me but are good for koi-only ponds.  Have you checked your pond pH?  Tannins will usually lower the pH so if your pH is below 7, it could be from the same problem causing it to turn tea color.  Tetra flakes may create a small oil slick on the surface but won't turn the water tea brown.  I suspect your mulch.  Add some activated carbon in a mesh bag to the filter.  That should remove most of the tannins.  You may need a lot of carbon.  Good luck!