Spraybars and Circulation Pumps

[foxfish]

Hi Charlieh, i would agree about the needle wheel pump but i am confused about your spray bar comment!
You say the flow would be less if you extend the spray bar & add more holes! I don't quite see how this would happen, surely this would offer less restriction and if anything increase the actual flow rate?

 

[Greenview]

Thanks charlieh. Yes, I had wondered if you could do something like that; it Seemed logical to me, just was not sure of the hardware. But my original post got lost in the debate that followed and I bought another filter instead. It cost a little more than a pump but I do have more biological filtration that way. The flow is now far better distributed with spraybars along the back wall of the tank.

 

[Charlieh]

Hi Foxfish. What I am saying is that the resistance to flow of a number of small holes will always be greater than the resistance of a single hole with the same cross sectional area of all the small holes added together - primarily because of the increased turbulence at each hole. The smaller the holes the higher the resistance and adding more and more can't increase the overall flow beyond what is being supplied by the pump. It's the same principal to placing a grill across a fan or an air duct - fine grid = more noise and less flow.