Aerating a top drip?

[YYZ Skinhead]

When I grow hydro in a 14-gallon Rubbermaid Roughneck with a timed intermittent top drip and an aquarium heater, will I get better results if I add a bubbler? The roots are never completely submerged because I only use 6 gallons per watering. I get very good results with it as is, but if adding a bubbler will aid growth, I shall plop my aquarium pump into it and bring on the bubbles.

 

[AluminumMonster]

I honestly don't think it could hurt anything...more oxygen in the root zone is "more gooder" in my book

 

[trillions of atoms]

If its ebb and flow and running chem ferts you don't need it. If your running organic w teas etc then yes.


Top feed like ebb and flow the nutes are just sitting if you mix a solution and have it sit for a week and its just watering once a day then I would air for good measure anyway. But if your feeding a few times a day w the ebb then the air isn't needed.

Adding air will increase temps if the room temp is higher than the Rez temp.

Chillers fix this.


I run air in any sitting solution

 

[trillions of atoms]

And how cold is the water? I'm suprised you need a heater already but idk where your at in the world

Still hot here.

 

[YYZ Skinhead]

I have an enclosed recirculating drip that runs lukewarm water for 30 min every 4 hours. I always use Foothillhydroponics.com Xtra-edge Grow, Bloom and Hard Water Micro synthetic ferts. I dunno why but the water in the reservoir is usually too cold unless I use a heater. I had root rot when I first started using the Rubbermaids, but when I added a heater I got fat, white, healthy roots. (I'll post pics wheb I get my upcoming grow started.)

 

[Growdude]

I dunno why but the water in the reservoir is usually too cold unless I use a heater. I had root rot when I first started using the Rubbermaids, but when I added a heater I got fat, white, healthy roots.

Yea that's strange its usually the other way around.

What is the temp? I like 68-72f

 

[YYZ Skinhead]

Yea that's strange its usually the other way around.

What is the temp? I like 68-72f

Same here. High 60s, low 70s. When I was growing in San Francisco, which is of course colder than Hell, I never had root rot, but I was growing in a shallower reservoir. I move down here to Hell where summer is 94 degrees in the shade (this past Saturday) and 6 gallons in a 14g reservoir is too cold. :doh:

 

[effdecaf]

Guy at the good local shop made this claim for not bubbling through your res: Bubbling through a res mostly increases air temps. The bubbles aren't adding oxegyn or dissolved gasses until they pop at the surface. Many aeroponic/outdoor growers incorporate waterfalls specifically for this purpose, the descending steps add DO at every level, as the water breaks its surface and creates more open surface area for the gas to get dissolved into the liquid. Bubbling in your res (as mentioned by trillions of atoms above) increases temps in proportion to your air temps. This also introduces contamination and yeasts from the surrounding air. (comment: I've seen people put their pumps in filter boxes).

 

[YYZ Skinhead]

That was something I was wondering, if the recirculating water running through grow rocks contained dissolved oxygen since it is perpetually hitting air for the 30 minutes the pump runs.

 

[trillions of atoms]

Yeast and anything else that might be floating around in there. But if you have a microbial herd they fix that quick.

Running chem nutes is nice n clean for me.


I have started an organic pbp this run tho for kicks.

 

[trillions of atoms]

And we all know its the surface tension breaking that arreates the water... Well I would figure we all knew that.




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*And I'm sure circulating will arreate the water somewhat, but how much? Does the run back have a good flow w the top drip?

If the water has been cold? If so then the dissolved o will stay longer.

 

[YYZ Skinhead]

And we all know its the surface tension breaking that arreates the water... Well I would figure we all knew that.

I knew that and thought that, but I had forgotten for sure, so I asked.

 

[trillions of atoms]

 

[effdecaf]

I knew that and thought that, but I had forgotten for sure, so I asked.

I'm super new to hydro so this blew my mind, never really thought about it that way (bubbles in solution arent dissolving any gasses etc)... In lab we always bubbled gas through the reactants to dissolve them lol!!

 

[Hushpuppy]

The bubbles still dissolve some gasses in the water as it is still air passing through the water. If you watch a large bubble very carefully, or see it filmed and then shown in slow motion, you can see that an air bubble doesn't actually move independently through water without breaking the surface tension of the water. The air actually pushes up through the water, breaking the surface tension and displacing the water directly above it. In slow motion you can actually see the water being displaced and cascading around the air that forms the bubble. For this reason, bubbling is a very effective method for dissolving oxygen in water.

But cascading, surface bubbling, and any other method that breaks the surface tension of water will also effectively aerate water. The problem with something like top drip or DWC is that there is little to no fresh oxygen getting to the reservoir where good oxygenation is needed to prevent anaerobic microbe growth. Having a pump constantly pushing fresh air into the reservoir eliminates that problem

 

[YYZ Skinhead]

But cascading, surface bubbling, and any other method that breaks the surface tension of water will also effectively aerate water. The problem with something like top drip or DWC is that there is little to no fresh oxygen getting to the reservoir where good oxygenation is needed to prevent anaerobic microbe growth. Having a pump constantly pushing fresh air into the reservoir eliminates that problem

Ah. Of that I wasn't aware, but it makes perfect sense. I may have been getting away with my top drip because I cut one extra-big hole in the lids so I can reach in and adjust the pumps, heaters et al. (I was hoping you would jump into this thread eventually because my drip rigs sound a lot like yours. )



addendum: reading all these posts about dissolving gases in water made me need to drink a seltzer. Mmmmm...seltzBUUUURRRRP!! :spit:

 

[effdecaf]

Correct me if I'm wrong but should not breaking the surface tension of a bubble moving through water disperse it into smaller bubbles and the displacement you speak of is the surface tension pushing through the water? If it indeed breaks the surface tension of the bubble, shouldnt smaller bubbles come off the main area that was being held by the surface tension until each bubble can reclaim some surface energy and create that energetic tension bond? Just a ponderance, as cascading def has greater oxygenation than bubbling, even though bubbling may increase some aeration (from what I understand from the popping on teh surface, each bubble would release some oxygen into the water but most likely most of it into the air because the air has a much lower resistance to the gasses inside than the solvent its interfaced with [res water/water])...

The bubbles still dissolve some gasses in the water as it is still air passing through the water. If you watch a large bubble very carefully, or see it filmed and then shown in slow motion, you can see that an air bubble doesn't actually move independently through water without breaking the surface tension of the water. The air actually pushes up through the water, breaking the surface tension and displacing the water directly above it. In slow motion you can actually see the water being displaced and cascading around the air that forms the bubble. For this reason, bubbling is a very effective method for dissolving oxygen in water.

But cascading, surface bubbling, and any other method that breaks the surface tension of water will also effectively aerate water. The problem with something like top drip or DWC is that there is little to no fresh oxygen getting to the reservoir where good oxygenation is needed to prevent anaerobic microbe growth. Having a pump constantly pushing fresh air into the reservoir eliminates that problem

 

[Hushpuppy]

Effdecaf: Oh no, you are getting very technical on me :doh: and I don't know as much of the very technical nature of this. I have to use educated conjecture here If there were enough internal pressure within the air bubble moving through the water, yes it could cause it to break into smaller bubbles, and this can be seen many times upon initial intrusion of large gas bubbles into water. However, with the bubbling of a small pump that drives out bubbles deep into the given body of water(depending on the constitution of gasses and the many variable of any solution), the pressure of water pushing against the air bubble, in relation to the air pressure within the air bubble will cause the bubble to stay intact and only its upward pressure is enough to break the water tension at the very center of the top of the bubble and force the water to cascade around the somewhat compressed air.

The natural pressure and friction on the molecules in both the air and the solution will cause some of those molecules to trade places. This friction and pressure combined with the cation/anion ratios will cause some of the gasses in the air to move to the solution that has less of those gasses, and vice-versa(even when the water tension has not been broken). Which method of aeration works better I honestly don't know.

YYZ: You are probably getting just enough aeration through the top of the medium to keep it from being a real problem. But I think some form of "extra" aeration will serve the plants better though