With technology evolving and the fish keeping hobby moving with the times we are getting closer to recreating the natural environment for tropical fish all the time. One key change in recent years has been the lighting options available for aquariums, this is a key factor in achieving the “shimmer effect”.
The shimmer effect is where you can see shadows and reflections underwater inside your aquarium, these are normally fast moving and in the sea, lakes and rivers are due to the waves on the surface of the water reflecting and bending the light from the sun.
This effect can now be recreated in the aquarium with 2 essential parts, firstly you will need to use LED lighting, this is due to the focused and direct light output an LED gives compared to other types of lighting options. The more powerful CREE style LED lights give a stronger effect than standard LED’s because there are fewer of them and are more focused than a strip with hundreds of normal LED’s in it. These types of lights emulate the sun more than say a T8 light tube. You must also be sure to only use these LED lights and not use them alongside tube lighting otherwise the tube will drown out the effect and it won’t be evident.
The other thing we must emulate are the waves, which is simply done with the output of your filter and powerheads, which all should really be pointing towards the surface of the water in your fish tank anyway to ensure there is a good enough level of oxygen exchange at the surface of the water.
It really is as simple as that, to get the shimmer effect in your aquarium you need surface water movement and use high power (CREE) LED’s only for the lighting.