Algae Control – Algae Tips

Read some of our tips on how to properly care for algae overpopulated ponds.

Evaluating Ponds and Algae

Algae Treatment Information

Listed below are some of the tips for having more clear water:

What to do if your pond turns green!

If the water in your garden pond becomes cloudy and turns green, it is most likely caused by an over-population of algae.

What are algae?

Algae are tiny plant-like organisms which are found just about everywhere on earth – in the sea, in our rivers and lakes, on soils and rocks, and in your garden pond. There are over 44,000 different types of algae, and mostly they are not, in themselves harmful. They contain the substance that makes all plant life green, (chlorophyll) which is used to convert sunlight into energy and food.
Every garden pond has a unique mini eco-system with lots of living organisms, including algae. A healthy pond is one in which everything is in balance. If the conditions in your pond favor the growth and multiplication of algae, they can over-populate the pond, and that is when you notice the water becoming green and cloudy. The objective is not to totally kill off all the algae, but to keep the pond balanced and the pond water stays clear.

What causes over-population of algae?

There are many factors and combinations which cause algae to over-populate. Knowing a little about these will give you a guide to the best actions to keep your pond in balance.

Sunlight and Water Temperature

Come summer, the days are much longer, the sun is more directly overhead and therefore can penetrate the pond water much further. It puts heat and light into the water. That is why algae problems usually become apparent in the summer months.

Oxygen Content of the Pond Water

Some think, the more oxygen in the water, the more it will retard the growth of algae. This is only a factor if the D.O. (dissolved oxygen) level is below 2. Many times, adding air can cause more algae to bloom. Microbial balance is the key using BioWorld.


The main nutrients consumed by algae are what are known as phosphates, nitrates and ammonia. All pond water has some nutrients present; the objective is to keep it in balance. Sources of nutrients include: – decaying vegetation (leaves, twigs, flowers, seeds), fertilizers, dead organisms (insects, fish, snails etc), fish droppings and excess fish food.

Actions you can take to reduce algae.

Please understand that every water garden is different and there are many different causes and combinations of factors which lead to over-populations of algae. Therefore, it stands to reason that each pond will have its own best solution. Your task is to discover what works best for you. This might take some time, and you may go down a few dead ends, but when you get everything back in balance, the algae population will reduce, and your pond water will be fresh and clear.

BioWorld can assist you with some of the additional equipment mentioned below.
Use BioWorld Algae Treatment in Sufficient Amounts to Get Rid of Algae Overpopulation

The continued use of the BioWorld Algae Treatment will allow the microbial life in the water to balance and stabilize. The reason undersea photos of whales in the ocean appear so clear is the water is in balance. Whales consume tons of microscopic creatures and algae to feed their giant body, yet the water looks to be totally clear. This vast amount of water in the ocean has an ecosystem that stays balanced with the nutrients, pH, temperature, sunlight and countless sea creatures including microbial life.

Your pond has a fragile ecosystem that can change temperature, pH and nutrients in a matter of 60 minutes. The water system is always unstable and needs help to accomplish some success in this very fragile ecosystem. Adding the BioWorld Treatment will provide the best opportunity to have this balancing act perform and clear the water as desired. Get rid of algae overpopulation with BioWorld Algae Treatment!

Removing Water

Remove 25% to 75% of the water every 7 to 14 days and replenish with clean, fresh water. Add the BioWorld Treatment after refilling. Sometimes the pH will be high and the algae likes pH of 7.6 and above. Lowering the pH will take time and patience through replacing the water. Caution: Do not be tempted to add pH buffers unless you have really done your research.

Shade the Pond Water if Possible

By shading the pond water, you will reduce the amount of light reaching the algae, and keep the water temperature lower.

Install Water Displays if Desired

If the water becomes stagnant, increase the oxygen content of the water with pumps.

Create a Biological Filter Zone

It sounds very technical, but it is actually very simple. A biological filter zone is created by grouping together special types of pebbles and rock-like minerals, through which you pass slowly moving water. The BioWorld formulation has the proper strains for the filters to work as intended.

Add more Water Plants if Desired

Water plants restrict the growth of algae by competing for the nutrients and blocking the sunlight. Place them in shallow “planting zones” around the edge of the pond. If you leave them in containers, you will be able to move them around easily. The bigger the pond, the more plants you will need.

Add Fish if Desired

A few fish can assist with algae balance, but too many fish will make the problem worse by their droppings and uneaten fish food. It all depends on the size of your pond.

Skim the Pond

Remove excess organic debris from the pond – a net will make the job easier.

Minimize Nutrients – Reduce fish food use. 

Look closely at possible sources of excess nutrients. Make sure that water run off from lawns or garden beds is not entering your pond.

Add a UV Filter or Ozone

A real unit is a fairly expensive solution, and we would suggest you try other solutions first. These are electrical devices which create ultra violet light (UV) in a glass tube through which you pass the pond water. The UV kills off the algae and other organisms which pass through it. (Do not purchase a cheap unit – you will have minimal results).


You need to tackle the root causes of algae by using the safe Advanced BioTech. Algaecide is a poison which you can add to the water to kill the algae. Admittedly it is a low concentration poison with low toxicity, but it is a poison nevertheless. For that reason we do not recommend its use in small ponds.

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