What is a RDWC's Gallon Per Hour (GPH) recirculating sweet spot?

[IamN2pot]

I'm curious to know. Is it a straight GPH number?
Is it a number of times per hour to turn over the total amount of water? example - turn over every 15 minutes. So a 10 gal system needs 40GPH and a 50 gal system needs a 200 GPH pump?

How does one figure that sweet spot for the recirculation pumping rate in a RDWC?
Thanks!

 

[Aqua Man]

I'm curious to know. Is it a straight GPH number?
Is it a number of times per hour to turn over the total amount of water? example - turn over every 15 minutes. So a 10 gal system needs 40GPH and a 50 gal system needs a 200 GPH pump?

How does one figure that sweet spot for the recirculation pumping rate in a RDWC?
Thanks!

Turnover… 4x/hr min 10x/hr ideal more may start to cause to much movement causing root damage but thats where pipe size of return and supply needs to be looked at

 

[IamN2pot]

Thank you, Sir!

 

[tobh]

excellent question. i have the calculation for a larger system using 3" returns, forget what my total volume was. iirc the pump I identified would work best was an outboard mag pump; big boy toy.

 

[moe.red]

If your return is smaller than 3 inches a lower flow is recommended so roots aren’t sucked into the return and block it. I flooded because of this once.

 

[Cool_Beans]

Variable speed pumps @steamroller recommended are perfect for tuning flow.