Green Garden Pond Water Problem

There are a kind of a few different causes, it can one, two or a combination of all.

Green Garden Pond Water

We are looking at the food chain and an imbalance of one or two items in the food chain. All will be explained, but first what is or why does the pond water turn green.

The green colouration in your water is Algae, microscopic floating Algae. Microscopic, you say, why can i see it, because there are literally millions of them. Algae can build very quickly if it has no deterrents, especially in the summer where the conditions are perfect and the nitrates and phosphate levels are high.

Algae is an informal term for a large and diverse group of photosynthetic eukaryotic organisms. Now I did rural biology at school, so I have no clue what I just wrote, but I hope some you did. Algae under a microscope has a blue pigment, but under water and sunlight it has a green glow. Therefore, millions of organisms in our ponds make it look green.

Algae feeds and breeds on nitrates and phosphate in the water, nitrates and phosphates are produced by fish waste, rotting leaves, sludge and other debris on the floor of your ponds. The first solution is to dredge out your pond bottom, removing all waste and decaying matter. I use a small fish net, like you see at the fair ground and regularly remove the waste, a very simple remedy. It reduces the build up of Nitrates and Phosphates which in turn starve the Algae of food.

Now Algae is no way harmful to fish, but we like to see our fish.

Now this I totally understand. I have used words of Imbalance and the Food Chain, this is where it all comes together.

Mother natural has its way of producing and taking away life, as one thing is created, another one comes to feed on it. Algae has one main predator or is the main food source of Zooplankton

Zooplankton are a family organisms, mainly salt water, types which include the radiolarians, foraminifera’s, and dinoflagellates, cnidarians, crustaceans, chordates, and molluscs. These feed on the Algae which cause a natural ecological balance and the water remains clear.

You may have read else where, too many fish are a cause to turn your water green. This is true and not true, what happens is, the fish like to eat Zooplankton and if they are not regularly fed, fish will turn to eat the natural food which is Zooplankton. They do eat small amounts of Algae, but not enough, therefor irregularly fed fish will snaffle up all the Zooplankton leaving the Algae to breed.

There are two natural solutions here, feed your fish adequately or you can buy and add Zooplankton to your pond.

There is always a chemical remedy which will return the balance to normal or kill the Algae.

Modern technology has had a major breakthrough in curing the problem of Green Pond Water.

Ultra Violet Light destroys the ultra fine planktonic Algae that causes your green pond water. Provided you have pond pump you can attach a UV Clarifier, this a UV light bulb encased in a tube and the water passes around the bulb which kills the Algae.

UV Light Bulb

Depending upon the size of your pond will depend upon the size / Wattage of the UV Bulb required.

They range from 7W Bulbs to now 55W Bulbs and relatively similarly priced. Range from £8 to £14 plus delivery. They recommend changing a bulb every 6 months, personally, my pond water is still clear after 18 months. Therefore this is the best solution and a very cost effective method to keeping your garden pond clear and free from Algae.

Below is a rough table guide to which bulb you should require

The next question is: How many gallons of water are in my pond?

A simple equation: Average Length in Feet, multiply by the Average Width in Feet, multiply by the Average Depth in Feet = Average Volume. You the multiply that by 7.48 Gallons (there are 7.48 gallons per cubed foot)

My pond is 10 ft by 4ft by 3ft, 10 x 4 x 3 = 120. 120 cubed feet x 7.48 Gallons = 897.6 Gallons

Given the rough guide I would need a 10w to 15w Bulb, I have a 11w bulb and this works perfectly. Proven Theory.

This is the route I went down, my pump was a bit old, just like myself, so I went for the All-in-One option. A build in UV light and pump, PRESSURISED POND FILTER PFC-5000 KIT - WITH FPP 3500L/H PUMP from All Pond Solutions in the UK. I purchased online and it was delivered in 4 days. Easy to install and works perfectly. Since installing this I have had zero problems with green algae.

Pressurised Pond Filter 5000

PRODUCT DESCRIPTION Our range of pressurised pond filters with built-in UV clarifiers are designed to be continuously pressurised by your pond pump, maintaining excellent water quality for healthy fishkeeping.

Water can be fed directly from your pond pump through to the filter container and subsequently the outlet, continuously under pressure. The water outlet can be located higher than the actual filter body, making it easier to disguise around the pond - particularly useful if incorporating a waterfall!

Supplied with a fantastic new rotating cleaning handle on the head, maintaining the pressurised filter is now even easier! The unit will inform you when it is in need of a detailed clean using a small float, which pops-out of the head of the unit when required.

By simply turning the handle you can rinse clean the interior sponge, reducing the need to dis-assemble! Once rinsed, a separate outlet can be opened to discharge any dirty water until it runs clean and basic maintenance is complete.

Each unit is supplied with a built-in UV light, which effectively prevents growth of algae and eliminates harmful micro-organisms and parasites which may cause fish diseases.

The Filter Specifications

• Decorative Ponds: up to 5000 Litres
• Ponds with a small mix of fish: up to 3000 Litres
• Ponds with a small mix of koi: up to 1500 Litres
• Maximum Pump Flow rate: 6000L/h
• Power of UV-Clarifier: 11W
• Voltage: 220-240v
• Cable Length: 5m
• Dimensions: 310 x 310 x 405 (mm) (L x W x H)
• Filter Compartment Volume: 16 Litres
• 3 x stepped hosetails fits: 20, 25 and 32mm
• Free 24 Month Warranty

The Pump Specifications

• FPP-3500 Pump
• Model: FPP-3500
• Max Height: 250cm
• Flow Rate: 3500L/h
• Outlet fits 25mm Flexible Hose (multi-stage hosetail also supplied can fit 20-38mm)
• Dimensions: 267 x 223 x 132mm
• 10m of Cable
• Watt: 42w
• Voltage: 220-240V

It goes without saying, the position of your pump inlet and outlet should be at either end of your pond.