How much flow does a coral need?

[ShepherdReefer]

I have been searching for the question, how much flow a coral need? When purchasing corals, the instructions usually state low, medium, or high flow but that does not tell me anything. I discovered a Youtube video by Vivid Aquariums entitled "Defining Low, Medium, and High Flow in a Reef Aquarium" and they suggested using the tank only volume of seawater. For example, if you have a 50-gallon tank, use the inter measurements for the calculation and when I did, it was around 45-gallons of seawater.

• Low flow usually around 10 to 15 times per hour
• Med flow usually around 15 to 17 times per hour
• High flow usually around 20+ times per hour

So, using the 45-gallons of seawater for each of the above, I get

• Low 450 - 675 gph
• Med 675 - 765 gph
• High 900+ gph

Just wanted to get the channel's throughs.

 

[HD_Reefer]

Interesting. Probably a good starting point.

 

[Rubberfrog]

Sounds in the ballpark