First time hydro: Ebb/Flood - DWC Hybrid

[Cannabinoid]

Hi guys,

i've been growing for some time on soil and deceided it was time to try something new.
So i started researching hydroponics.
From what i've read ebb & flood and dwc setups are most common and they get good results.
My idea (i'm likely not the first to think of this) is to combine the 2 into a hybrid system.

Like shown in this drawing.
But since i've never grown hydroponic i'm asking you guys if it would work and if it outperforms a "standard" system.

Greetz

 

[Heath Robinson]

Hi Cannabinoid, I cant tell from your diagram how you would flood the top pot, wouldnt the water simply return down the water return pipe?.


Heath

 

[Al B. Fuct]

Hi guys,

But since i've never grown hydroponic i'm asking you guys if it would work and if it outperforms a "standard" system.

New hydro growers should not to try to invent new systems before they've mastered the traditional ones.

Your design would work but there would not be any significant performance advantage to a traditional flood system:

Missing from this animated diagram from SimplyHydro is an air pump & air stone in the nute tank.

Use of media which tolerates frequent flooding like Fytocell, perlite or clay pellets allows the roots to be bathed with oxygenated nutes several times during a lights-on cycle, accomplishing what your proposal does.

I think your design, though functional, would be hard to work with in practise. It's nice to have plants in individual pots of media so they can be moved around within the op for maintenance or placing slow plants in preferential light positions. Your system would not lend itself to individual pots. It would also be hard to fully drain your system at tank change time.

 

[Cannabinoid]

@heath: I forgot to draw the pump,water would be pumped up throug the water return pipe.

@Al B: You pointed out some major downsides to my design,thanks.
I'll follow your advice and start with a regular ebb/flood setup.
One thing i don't get about it: why should there be a bubbler in the nute tank?
Is it to aerate the tank and if so,why?
Wouldn't the water be aerated when being pumped into the top pot during a flood-cycle?

Greetz

 

[Al B. Fuct]

Is it to aerate the tank and if so,why?
Wouldn't the water be aerated when being pumped into the top pot during a flood-cycle?

Yes, it's there to aerate the solution, to increase the amount of O2 dissolved in the water. The main thing that makes hydroponically grown plants more vigorous and thus productive is the ability to get more O2 to the roots.

No, a submerged pump won't aerate the solution. It just moves it around.

Many centrifugal aquarium pumps as sold for this purpose include a venturi fitting and a rubber tube with a float/liquid separator. The motion of the water past the venturi draws air down the rubber tube from the float on the surface.

While this apparatus will make bubbles, it is neither sufficient nor efficient aeration to dissolve O2 in the solution. It takes more exposure to air bubbles than just when the water is being pumped into the trays to obtain sufficient oxygenation.

Rememeber, air is about 73% nitrogen and only about 20% O2. An air pump and bubble curtain running in the nutes 24/7 will introduce signifcant amounts of O2 to the soln.

 

[Heath Robinson]

If the overflow pipe was cut to the hight of the water return pipe it would work very well. It would then be the same principle as the recirculating system I use and you wouldn't need the bubbler in the top pot as the recirculating action would provide plenty of DO.

good luck whatever you decide to do.




Heath

 

[Al B. Fuct]

If the overflow pipe was cut to the hight of the water return pipe

If he did that, only the pellets on the very bottom of the pot would be wetted. Roots won't much like the areas of pellets that are not frequently flooded. Roots would form mainly around the very bottom of the pot if the overflow tube were shortened.

 

[Heath Robinson]

If he did that, only the pellets on the very bottom of the pot would be wetted. Roots won't much like the areas of pellets that are not frequently flooded. Roots would form mainly around the very bottom of the pot if the overflow tube were shortened.

Have a look at this pic you can see the water level on the tub, above that line there are dry pebbles below is the recirculating system and the resulting root mass.

 

[Al B. Fuct]

Have a look at this pic you can see the water level on the tub, above that line there are dry pebbles below is the recirculating system and the resulting root mass.

Yep, that's precisely the effect I predicted with the proposed system with a short overflow tube. While your root development is spectacular (noice work ), this is DWC, which really isn't for noobs.

I encourage beginners to use flood systems which contain the rootmass within the pellets for several reasons, including plant portability. The pellets in the pots won't be homey for roots unless frequently flooded.

 

[Heath Robinson]

lol I will leave it here we could go on forever! its actually shallow water culture as there is more medium than water


Heath

 

[Al B. Fuct]

OK, SWC (aero? ) then. Still looks great, good job.