Dissolved oxygen help

[nicksol86]

Hi, wondering what the best way to aerate res? Currently have 2 general hydroponics dual diaphragm pumps cuz they're quiet when they run. I have one 4 inch air stone per 5 gallon bucket. Is this sufficient? Or is there better ways to add oxygen to my res? Ran my first dwc grow a few years ago and used air stones with no problems, but is there a better way to add Dissolved Oxygen for hydro 5 gallon single buckets?

 

[rkymtnman]

waterfalls create more DO than airstones.

 

[nicksol86]

waterfalls create more DO than airstones.

OK well what kind? Submersible or not submersible? Which is better or the best? Got a link to something I can see so I got an idea for when I shop

 

[OldMedUser]

A waterfall needs a water pump and in DWC you generally just have an air pump so it would be a PITA to set up a waterfall. The airstones should be fine and all I've ever used for my DWC. I use Rubbermaid tubs but may need to find another brand as the new tubs use a different plastic to keep them soft in the cold and I'm sure it screwed up a recent attempt to run two tubs. Zero root growth after 2 weeks and small clones dying so transferred all the plants into pots of soil/soilless and they are doing fine now.

I've done about 50 tubs in the last 16 years and never had that happen. Using 2 - 12" airstones and an EcoAir commercial air pump putting out 600gal/hr so I had lots of DO. Years back I just had one stone per tub and a small aquarium air pump on each and that worked fine too.

Good luck and good growing!

 

[ANC]

You can buy a hang on aquarium filter, It has a long pickup tube and a waterfall that falls back into the tank/reservoir. I would fill it with ceramic media and grow some bacteria on it to help feed the plants

The best way to control O2 is through temperature control end of story.

 

[OldMedUser]

The best way to control O2 is through temperature control end of story.

Explanation?

 

[ANC]

regardless if you waterfall, stir, bubble, propel the water with the jet from a 747, the percentage of O2 changes minute fractions compared to simply reducing the temperature...

 

[OldMedUser]

regardless if you waterfall, stir, bubble, propel the water with the jet from a 747, the percentage of O2 changes minute fractions compared to simply reducing the temperature...

The temp only changes the amount of O2 the water can hold and it's not a huge difference between 65F and 70F. Maybe 3% more in the colder water. The plant is still using up the oxygen and it needs to be replenished somehow.

I can chill my water down to 50F if I want but unless I add more air to the water it will eventually be depleted. Temperature alone won't keep O2 levels up. Not that plants are going to thrive in 50 degree water. 65 - 68F is the zone to keep O2 levels higher and retard the growth of pathogens while encouraging rapid plant growth.

 

[ANC]

I suppose being a fishkeeper, which is a nice way of saying you keep water fresh, turnover by way of a pump is always part of the picture.
Indeed O2 moves pretty slowly through water and you have to expose it to the surface by movement to get O2 in the water. Or use lights and plants and CO2 to get above 100% O2 saturation or as some do, bubbles to lift water from the bottom and carry it to the surface.

 

[OldMedUser]

Just the air bubbles create circulation to mix the water up and the bubbles dissolve into the water as they rise to the surface adding their gases to the water. Smaller bubbles are better as they have much more surface area per volume of air and more readily add their gases to the water.

In our dugout I used a 50ft garden seeper hose on the 1/2" air line that runs out there from the aerator in my basement. It was anchored at each end and in the middle so it forms a big m under water. Where the tops of the m are there were millions of tiny bubbles but where the hose was lower you could see the bubbles rising to the surface but they disappeared before reaching the surface. Had the best water ever during the winter after that but need a new one now. Just going to leave it rolled up from the store and use a piece of scrap metal tied to the roll to hold it down.

A buddy has a huge fish tank with all sorts of things in there, CO2 for the plants and everything. Breeds and sells fish for extra cash. Has smaller tanks all over the house. Sells pot clones to growers for even more cash.

 

[Airwalker16]

Waterfalls are my next upgrade. I already use them in rdwc now but I want to ELIMINATE the loud ads annoying air pump from the picture completely. My only problem now is 1" vinyl tubing gravity return lines. Upping to 2" black ABS and Uniseals that way I can put my pump on full power and BLAST water into each bucket. I use an elbow from the inside of the bucket coming OUT the grommet and connect my hose that way so the water is going straight down at the water. I just can't now, because the lines aren't big enough to carry the amount of water the pump drains from the res to replenish it and keep it full. Very excited for this upgrade.

 

[OldMedUser]

Won't the sound of gushing water be loud too? Would make me want to go pee all the time.

I always have the radio on loud so I can hear it when the exhaust fan cuts in and drowns out the quiet hum of the air pump and the radio. Pumps etc are down in the bunker and can't be heard upstairs so noise isn't a concern for me.

 

[OldMedUser]

Waterfalls are my next upgrade. I already use them in rdwc now but I want to ELIMINATE the loud ads annoying air pump from the picture completely. My only problem now is 1" vinyl tubing gravity return lines. Upping to 2" black ABS and Uniseals that way I can put my pump on full power and BLAST water into each bucket. I use an elbow from the inside of the bucket coming OUT the grommet and connect my hose that way so the water is going straight down at the water. I just can't now, because the lines aren't big enough to carry the amount of water the pump drains from the res to replenish it and keep it full. Very excited for this upgrade.

Won't the sound of gushing water be loud too? Would make me want to go pee all the time.

I always have the radio on loud so I can hear it when the exhaust fan cuts in and drowns out the quiet hum of the air pump and the radio. Pumps etc are down in the bunker and can't be heard upstairs so noise isn't a concern for me.

Something I've wondered about setups like the one you are doing is where does fresh air come from to mix into the water?

The same volume of liquid coming in is going out and the only air is in the headspace above the water level and below the lid. There's nothing to draw fresh air in all the time like is added to the water with airstones.

Not saying it doesn't work but it seems odd that it does. I'd sure like to have a DO tester to see just how well each method actually works. I know for sure that the pair of stones and good pump put way more air into the water than the plants can use so it's overkill but with aeration more is always better.

 

[PetFlora]

I use 2 pumps in each rez. On is to pump nutes into F & D totes, the other is small and on a deep cycle timer, so as to keep pump from heating the rez. I run 2 minutes on/20-30 minutes off

Here one is in action. The other (not pictured) has a riser with an elbow above the water line > horizontal tube and elbow to direct back into rez

Incoming bulkhead to each tote is Active Aqua with diffuser