Anybody Found a Working Garden Pond Algae Remover?

We tried numerous Algae removal chemicals last year in our shallow 1500 litre, mostly shaded, goldfish pond to no avail.
It cleared over winter but is already back again now.
I thought I'd be able to use our cheap above-ground pool sand filter, but it won't work above the water surface level, so that's out.
The goldfish don't care but it looks unsightly.
Anyone know of an algae remover that might actually work in Brisbane (and not kill the fish)?
Ta.

Comments

  • +5 votes

    Snails

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    I don't know about ponds but for fish tank we use snails.

    The algae could be a sign that there's not enough oxygen or too much poop. Have you checked those levels?

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    Do you feed the fish? They probably don't need it, between the insects and algae they will eat otherwise.

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      Yeah, I know they don't need it, but they look at me with such longing in their little eyes as they follow me around the pond.
      We once had a disgusting algae-filled unused above-ground pool down the back that I eventually drained and found dozens of goldfish in that had never been fed.
      No idea where they came from, but they led to the creation of this pond, maybe 20 years ago now.

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      We've got shade cloth above most of it and overhanging plants (which may also contribute to the problem when bits fall in), so only a few square feet get the sun. Guess this is still too much. Hard to shade the remaining bit though.

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    Get an Ultra Violet Clarifier, that's the only thing that's worked on our big Koi pond.

    https://www.rockaroundtheblock.com.au/ponds/water-clarificat...

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    As ppl have mentioned, snails. But some snails are more effective then others so do your research. Also snails reproduce themselves so after a while you could have a snail problem (which you can easily fix by removing them with your hands)

    You can also consider getting a plecostomus (catfish)

    •  

      I looked up the plecostomus, but are they rugged enough to throw in an outside pond and ignore?
      Sounded like they need a bit of babying to thrive, not like my macho goldfish.

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    Copper sulfate, but find a NEW HOME for the fish first!!

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      Sounds drastic! Moving them to my bathtub sounds mildly inconvenient, in the long term…

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    Cloverleaf blanket answer pretty much guaranteed to fix it. It's a powder with bacteria and enzymes that suffocate and kill the algae (but don't affect koi fish). There's then Cloverleaf sludge answer liquid that breaks down the dead algae strands into beneficial waste for the pond. Takes 4-6 weeks process to go from opaque green goop to crystal clear water. We used to do it every year in the UK without fail. Works a treat but not sure if you can find it here.

    That fixes the existing algae problem but if you want to make sure it doesn't come back, you need a UV clarifier as mentioned above as part of your filtration system. Bulbs burn out once a year too so get replaced with the treatment. Don't forget to medicate pond annually too.

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    I have a pond with exactly this problem, made worse by feeding goldfish. I suffer from strong string algae/blanket weed that matts through the water and causes great obstructions and wraps itself around plants and pipes and filters. The only thing I got to work is a product called Green Away by Blagdon (new company name, I forget what it used to be called, Interpet?). It was available from Bunnings and various places but I haven't seen it around much these days. Might be a special order item. Unfortunately it is relatively expensive, you don't use much each time but it does add up. I had my eye on a one litre bottle for $50 + UK postage on ebay https://www.ebay.com.au/itm/181657675581. It kills the green stuff in a day or two, and a brown "dirt" will fall out of suspension onto the bottom of the pond. Water looks a bit strange and all brown for the first day, but it never hurt my fish or water plants. If you have a pump running the deposits will be removed from the pond and it will be crystal clear. I highly recommend the stuff, but it is expensive. You could try a small bottle but unfortunately you will still be paying a lot for shipping, unless there is a local supplier that can do a reasonable price.

    As with Hybroids answer above, they also have a sludge remover which converts any deposits left if you don't also use a pump/UV filter. The sludge remover IS available at Bunnings, but the Green Away doesn't seem to be available.

    Also, I tried adding aquatic snails to the pond but they all escaped to the garden! They never did a thing for me so I can't recommend them.

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      The Blagdon 250ml Green Away for Ponds (more than enough for my size pond) is only $26 on eBay, so I'll give it a go, I think. Thanks.
      Will also look at using a sludge remover. The pebbles on the bottom of the pond make it difficult to clean other than by draining, shovelling and washing.

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      Thanks. You don't say how effective it is though….some of the reviews sound troubling.

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