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How To Get Rid Of Blanket Weed In Your Fish Ponds ... Introducing "Goodbye Blanket Weed"

Blanket weed is a plant or to be more precise it is a form of algae. It loves sunshine and warm fish ponds.

Algae are plants and as such they grow through the process of photosynthesis. This means quite simply that if blanket weed algae spores exist in the pond and if there are sufficient nutrients dissolved in the water then when the sun shines and especially if the water is warm as in summer months then the blanket weed will take on a life of its own.

Once a fish pond has become "infected" with blanket weed it used to be virtually impossible to get rid of it. Thankfully there are blanket weed controllers, blanket weed cures, blanket weed removers and a whole host of other blanket weed treatments or killers. Not all of them work all the time and the reason for this is not well known but it probably revolves around the many different types of algae in the blanket weed class.

A side benefit of having blanket weed in your fish pond is that the pond water is generally very clear and herein lies part of the modern day secret to getting rid of blanket weed. Why does this kind of pond water stay clear? The answer is that the nutrients are taken up so greedily by the fast growing blanket weed (also called string algae or filamentous algae) that the tiny suspended types of algae referred to normally as green algae can't get a grip on life. They are virtually starved out of existence.

The Nutrients Required For Blanket Weed Growth

It's simpler than you think ... algae are plants (and mainly green at that) as I said and this means they love nitrogen and phosphorous. In pond water these chemical elements show up as NITRATES and PHOSPHATES and the nitrates are in turn produced by an in-pond process called nitrification. Don't worry too much about the detail of this nitrification process here save to say that fish are the source of ammonia and the ammonia is turned into nitrates by bacteria in the pond biofilter. Nitrate is dissolved in the pond water. What's very important is to recognize that nitrates and to a lesser extent phosphates are needed for blanket weed to survive.

No nitrates = No blanket weed.

So all we have to do is get rid of the nitrates. Unfortunately it's not quite so simple but Bradshaws now sell a couple of products that really do work and they work by mopping up nitrates dissolved in water. Removing nitrates by using specific naturally occurring bacteria mixtures was proven in independent tests carried out by Brooksby College to be the best way to control blanket weed. They discovered that by using the right bacterial mixes and regular treatment with the bacteria it was possible to reduce nitrates to extremely low levels.

During 2001, Brooksby College, the well known aquacultural college in Leicestershire, England, were asked to undertake some blanket weed trials by "Koi Ponds & Gardens" magazine. The results were published in the August 2001 issue of "The Koi Ponds and Gardens" magazine under the feature entitled "Beat the weed".

Six blanket weed control products were tested. Two were electromagnetic, one was a water purifier with a copper releasing cartridge, another was a water colorant and two of the products were microbial in nature.

Blanket Weed Goodbye Picture Nishikoi developed a bacterial treatment and gave it a most marvellous name ... "Goodbye Blanket Weed"

The product comes in sachet form and is a secret mixture of bacteria and barley straw extracts. It has become an award winning product and a top seller at Bradshaws.




How Do These Secret Bacteria Work In A Garden Pond?

Just as it was explained that blanketweed is more greedy than suspended green algae (the type that causes water to go like pea soup) the bacteria in Goodbye Blanket Weed are even more greedy for nitrate nutrients than the blanketweed itself and as such the bacteria starve the blanketweed out of existence. It's a process called competitive exclusion ... where 2 species compete for the same food and because life is such a great motivator for all species the stronger one will always survive best.

As the bacteria get used up then they must be replenished by adding the correct dosage to the water..

What is blanket weed?

Blanket weed spreads and recolonises vegetatively, by branching off and breaking off parts of its own structure which will then colonise new areas. Biologically speaking, this can be a risky strategy, as if the environmental conditions change, it does not have extensive means of adapting to the changing environment. However, where the environment provides consistent conditions, (as in a koi pond), and the blanket weed is adapted to those conditions, it is a very successful strategy, allowing it to thrive and spread rapidly throughout its life cycle.

There are numerous types of blanket weed (also referred to as string-algae). The most common general are Cladophora, Oedogonium and Spirogyra. Cladophora means 'branched plant' and when viewed under the microscope, it is possible to see the regular-branding filaments, each of which is divided by cross walls. Thanks to Ben Helm for this description.

Other Ways To Combat Blanket Weed and Control Its Rapid Growth In Fish Pond Water ... based on reducing sunlight, reducing nutrients, lowering temperature & killing the algae. Notice there are blanket weed control, removal, killer, treatment and blanket weed cures.

  • Reduce sunlight penetration into your garden pond water using blue dyes like Nishicare Blanket Weed and Algae Control. These are only partially effective based on the Brooksby College tests but do make a difference and are especially useful in very large ponds like those on golf courses. Create shade conditions around the pond ... the best way is to plant aquatic plants and especially plant water lilies with their large surface area leaves. Of course the water lilies also reduce nitrates as well. Floating plants do a good job of providing shade also. Very green pea soup algae ponds do not have blanketweed because not enough light can penetrate the pond water ... but we want a clear pond full of life that we can enjoy; there is little point in having pond water looking like a dense green pea soup, is there? This kind of approach would be classed as a blanket weed controller approach.

  • Nutrient removal in pond water is best achieved by using "Goodbye Blanket Weed" as described. Plants will compete with any type of algae for nutrients in the water and as such will help to deter blanket weed growth. This is a blanket weed remover process.

  • Blanket weed does not grow well in winter because the water is cold. I'm not suggesting you cool the water though ... it does help to control blanket weed but it is, not always practical.

  • Algaecides are a type of herbicide. Blanc Kit Excel supplied by the UK's leading koi food producer, Nishikoi, is an extremely effective one and safe in water and pond environments. With the use of off the shelf algaecides there is a need to be extremely careful of toxic side effects. Using Blanc Kit Excel is a blanket weed killer process. Whenever you use algaecides also read the instructions carefully and especially take care of any impact there might be on your pond bio filter. Fish are very sensitive to even minor concentrations of chemicals and filter bacteria even more so. Don't kill your bio filter whatever happens and this is why "Goodbye Blanket Weed" is such a good solution. If adding chemicals know the volume in gallons or litres of water in your pond quite accurately.

  • Barley straw or the more active and preferred barley straw extract take time to work. The process as to how barley straw or the barley straw extract works is complex and has to do with the in-situ production of hydrogen peroxide. This chemical is a very strong oxidising agent (bleach) and this probably interferes with the photosynthesis (green) process of growth.

  • For garden ponds that are high in calcium dissolved in water then electronic blanket weed controllers are claimed to work well.

  • If all else fails then you'll need a blanket weed remover and the best on the market is the EASY WEEDER ... what's important about this device is that it has blunt ends to ensure you don't puncture your liner. It's always a good idea to remove as much blanket weed as possible before adding any treatment of any type to your garden pond water.

A note about supplies and equipment from Bradshaws because we bank our 25 years reputation and our future success on our customer service and the free advice we offer.

Slick Professional Order Line & Customer Sales Advice

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