Comparing the 2 main RDWC designs (waterfall, undercurrent)

Experts or people with these systems, what do you like and what would you do differently?
Assuming 4 grow sites with 5 gallon pails/buckets.

Common pieces:

• 2-3 inch PVC pipes between the grow sites
• Air stones + air pump
• Water pump is inline and not submerged in the reservoir

Main Differences

1. Undercurrent system: Water is pumped from the returns from the last two grow sites, falling into the reservoir. E.g.: CCH2O
   Side question, could that cause some grow site reservoirs to have lower water levels? (saw some threads)
   
2. Waterfall system: Water is pumped from the reservoir, through 1/2-1 inch tubes, falling into the 4 grow sites. E.g.: PA Hydroponics
   Pipe splits need to be equal to have same water levels.

Verdant Vicar said:

what do you like and what would you do differently?

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Oh man.. uhhh.. I would of drilled smaller holes.. pretty much it for the waterfall part, I like the rest.

There is tons of info recently posted talking about all this. Search RDWC waterfall and check it out. Will link some here in a bit..

Verdant Vicar said:

Experts or people with these systems, what do you like and what would you do differently?
Assuming 4 grow sites with 5 gallon pails/buckets.

Common pieces:

• 2-3 inch PVC pipes between the grow sites
• Air stones + air pump
• Water pump is inline and not submerged in the reservoir

Main Differences

1. Undercurrent system: Water is pumped from the returns from the last two grow sites, falling into the reservoir. E.g.: CCH2O
   Side question, could that cause some grow site reservoirs to have lower water levels? (saw some threads)
2. Waterfall system: Water is pumped from the reservoir, through 1/2-1 inch tubes, falling into the 4 grow sites. E.g.: PA Hydroponics
   Pipe splits need to be equal to have same water levels.

Click to expand...

Waterfall setup allows you to ditch the air pump/line/stones entirely.

Airwalker16 said:

Waterfall setup allows you to ditch the air pump/line/stones entirely.

Click to expand...

I started to read that. Was there anyone who did a test with and without air stones?

Verdant Vicar said:

I started to read that. Was there anyone who did a test with and without air stones?

Click to expand...

I along with about a dozen other members here use waterfall setups with no airstones

Airwalker16 said:

I along with about a dozen other members here use waterfall setups with no airstones

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Awesome, one less complexity. The waterfall must not touch, be falling into the netpot/roots right? Some netpots I'm planning are not centered and on the corner (smaller plants, multiple).

Verdant Vicar said:

Awesome, one less complexity. The waterfall must not touch, be falling into the netpot/roots right? Some netpots I'm planning are not centered and on the corner (smaller plants, multiple).

Click to expand...

I wouldn't suggest the waterfall be running right on the roots, but ita pretty idiot-proof. Just have an inlet of water coming into the container with a few inches of distance for the water to fall.

Verdant Vicar said:

I started to read that. Was there anyone who did a test with and without air stones?

Click to expand...

I started with air stones, airwalker questioned why and then I swapped it to waterfall. Assuming DO went up, what I noticed is water stabilized even better, it circulated better, ph/ec readings quicker. It’s kinda like peace of mind, it’s just working and it works well. I don’t see why anyone would test the two.

Here’s what I ended up doing, there’s a lot of info and ideas and very knowledgeable people here on RIU.