How many water changes per hour for DIY RDWC Waterfall/Fallponics?

[Verdant Vicar]

We have seen conflicting information from multiple changes per hour to once every 1-2 hour.

What is the target number of water changes per hour for a DIY waterfall / fallponics system (PA Hydroponics) to each grow site?
What about for a DIY undercurrent system (like cch2o).

Much smaller scale, 3 x 15 gal totes returning to a 5 gal bucket reservoir. Total = 50 gal.
Then I could calculate the pump required and piping.

Looking to use an inline pump next to the reservoir to avoid heating up the water.

 

[GBAUTO]

My 4 tote UC style setup uses a 700gph mag drive with a 45 gal total.
I've used this setup for a couple of seasons and it works really well.

 

[Verdant Vicar]

I was calculating along this range. What is the model you use?

I have been looking at the SICCE Syncra Silent 2.0 (2000 litres per hour = 568 gph)

 

[GBAUTO]

https://www.amazon.com/gp/product/B01G0PVYY4/ref=ppx_yo_dt_b_asin_title_o06_s00?ie=UTF8&psc=1

This is the pump I run.

 

[Verdant Vicar]

Thanks!!! What size tubing and which connectors have you used?
Anything at the end to have a bigger splash agitation?

 

[fragileassassin]

My 4 tote UC style setup uses a 700gph mag drive with a 45 gal total.
I've used this setup for a couple of seasons and it works really well.

800gph on a 6 site 55 gal system here.
These examples are about as high as you want to go.

 

[JSB99]

We have seen conflicting information from multiple changes per hour to once every 1-2 hour.

What is the target number of water changes per hour for a DIY waterfall / fallponics system (PA Hydroponics) to each grow site?
What about for a DIY undercurrent system (like cch2o).

Much smaller scale, 3 x 15 gal totes returning to a 5 gal bucket reservoir. Total = 50 gal.
Then I could calculate the pump required and piping.

Looking to use an inline pump next to the reservoir to avoid heating up the water.

For a true UnderCurrent setup, you need a water pump that will cycle the total number of gallons, 12 times/hr. You wouldn't run the pump intermittently, but all the time.

For example, if you had 100 gallons in your system, then you would need a 1200gph pump.

 

[GBAUTO]

Thanks!!! What size tubing and which connectors have you used?
Anything at the end to have a bigger splash agitation?

This pump has a 1"npt inlet and 3/4"npt outlet, so I just run pvc in those sizes.
My inlet bulkhead is a 1 1/2" and I reduce that to 1" for the pump.
I currently use the mag drive to also circulate through the chiller but next year I'm going to use a separate 396gph pump for the chiller and use the 700 just for circulation/waterfalls.
I think the simplest method for a spray head is using a pvc cap that has multiple small holes drilled into the end to act as a showerhead.