At some stage in practically every aquariums life it will become the end result of an algae outbreak. Quite often these outbreaks simply disappear on their own, however on some occasions they simply will not go away and no matter what the aquarist does they simply return.
It is important to understand in the first instance why algae takes hold and grows in the aquarium.
All algae require an energy source. This energy source could be a particular colour temperature in the light, a nutrient in the water etc.
Therefore the algae outbreak could be due to the lighting not being replaced and the incorrect colour spectrum being transmitted into the aquarium. Some algae like this particular temperature and then grow. The light to the human eye will probably look fine however unless you perform a specialist test you will not know. The best thing to do is ensure that you change the bulbs at the correct time period based upon manufacturer’s recommendations.
The second and probably the most common one is where algae feed upon nutrients in the water. The most common nutrients and nitrate, phosphate and silicates. In this scenario especially for nitrate and phosphate it can be hard to locate. The reason for this is that the algae are taking up the nutrients from the water column and therefore when a test is performed the parameters appear to be ok. As soon as the algae is removed from the aquarium the levels start to increase and the algae takes hold again.
It is a vicious circle unfortunately.
As the saying goes though – prevention is better than cure.
The best prevention is to ensure that the equipment in the aquarium is correctly maintained and replaced if/when required as well as the water parameters being kept at the highest possible standard.
A very useful part of obtaining these parameters is the reduction/removal of nutrients. An excellent way to reduce and/or remove nitrate and phosphates is through the use of natural based control.
This natural based control could be live rock, deep sand beds, mud beds, refugiums, mangroves etc.
Live rock for example is exceptionally powerful at filtering the aquarium and if enough high grade quality is purchased then it can also assist in the reduction/process of nitrates.
It is my opinion that there are two natural based packages which can be used for both filtration and nutrient export.
- Live rock combined with a deep sand bed – This allows for efficient filtration of the aquarium via the live rock and also for nutrient export via the deep sand bed.
- Live rock combined with a refugium – This again allows for the efficient filtration of the aquarium via the live rock and also for nutrient export via the refugium where macro algae is grown.
In the refugium example above I personally find it interesting that you can use algae to control algae. The reason this can be performed is that the algae which you are growing in a separate aquarium can be harvested from time to time. The algae removes nutrients from the water and uses this for growth. When the algae is harvested from the aquarium the nutrients are removed as well. As you are not removing all of the algae then the remaining algae feeds upon the nutrients in the water and maintains these parameters at a low level. Because the algae is located in a separate aquarium no or minimal algae outbreaks should occur in the main display aquarium. This is not to say you will never receive any because you might however it severely reduces the possibility.
These are not the only methods which you can use as there are many more. Mangroves for example are very powerful but they are very slow growing and therefore reduce the nutrients at a slower speed.
The aquarist, however should never rely upon these techniques and needs to ensure that the correct care and maintenance is still employed, the fish are not overfed etc.
Simply put in response to the question in the title of this post – yes natural algae filtration does work as long as it is properly implemented and cared for.
Follow nature and keep it simple.