A refugium can be made from many things in the aquarium but for the concept of this article we shall classify a refugium as an area which contains a sand covering and macro algae being grown.
This type of refugium allows for two things to be completed :
1. A safe refuge for for animals to populate without fear of predation.
2. Excess nutrients to be removed by the macro algae growing.
The refuge aspect is created automatically simply by not introducing fish or other animals with feed on the little ‘critters’ into the area, For the excess nutrients to be removed though the macro algae needs to grow and for that it needs light.
Can you just use any light though?
As we are growing plantlife we need to use lighting which is designed for this purpose.
For reference the normal lighting we use above a [tag-tec]saltwater aquarium[/tag-tec] is between 10,000 kelvin and 20,000 kelvin so can we use that.
We could but that kelvin rating is not suited for plant growth – it is suited for corals. Corals require lighting which is in the blue to violet range of the spectrum. Although it would work the macro algae would probably grow slower than if you used lighting designed for aquarium plants. Macro algae (and the majority of aquarium plants) prefer lighting which is in the red to orange range of the lighting spectrum.
For this reason it is better to attempt to locate lighting which is between the 5,000 kelvin and 10,000 kelvin rating with the lower end being the preferred end.
The interesting aspect here is that you do not have to utilise lighting which has been designed for aquariums. It is the kelvin rating we are interested in and luckily for us there are loads of house based lamps in this area.
Simply pop along to your local household store and check out the lights, read the label and see what the kelvin rating it.
Of course if you do not want to do this then just go to your local fish shop and ask for a blub which is designed for aquarium plants.