[Cougra]

This subject isn't very easy or straight forward as water movement will depend on the type of tank that is being kept. The same turn over rate in same sized tanks set up in different ways can be just right, too much or too little.

While some people try to get as much water flow as possible such as SPS dominated tanks, other types of tanks can't have very strong water movement at all such as Seahorse tanks. Because of the wide range of conditions, substrates, rocks and animals that are available it's vitally important that people plan their tanks according to what they want to keep in the tank before deciding on the type and amount of water flow needed.

One of the more popular terms we see when talking about water flow is the turn over rate but what does this mean exactly to you? How do you measure your turn over rate?

I've read posts where people seem to think that it means how much water needs to flow from the tank through the filtration units and back into the tank again. But is it really necessary to have that much water flowing through a sump? In order for bacteria to do it's job there needs to be adequate contact time between the water and the biological filtration. It's possible to have water flowing through a sump too quickly, especially one that is being used for biological filtration.

Over the years that I've been reading forums and literature, I've found that there has been a lot of improvements in technology to help with good water flow and peoples general understanding of wahter circulation. It's interesting to watch how things are progressing in the hobby.

The one system that I would love to be able to find a way of putting on my tank is an actual wave maker, not one of those electonic things that turn pumps on and off in random order but a bucket placed above that tank that fills and empties quickly to create the most natural wave motions!