The necessity of airstones

[Rahz]

I run a RDWC with waterfall oxygenation but use bubblers both as a fail safe and as a means of keeping the roots wet til the hit the water. I've been playing around with ditching the stones and using some weights to keep the tubing submerged. Doing this provides enough splash to keep the net cup wet.

My question is whether tests have been done on O2 levels stoneless?

Initial thoughts:

Airstones make pretty bubbles which is useful in aquariums but not an issue in DWC.
Running without an airstone might affect the life expectancy of the air pumps due to pressure variations?

Anyone have opinions or facts related to running stoneless in DWC?

 

[Yodaweed]

I run a RDWC with waterfall oxygenation but use bubblers both as a fail safe and as a means of keeping the roots wet til the hit the water. I've been playing around with ditching the stones and using some weights to keep the tubing submerged. Doing this provides enough splash to keep the net cup wet.

My question is whether tests have been done on O2 levels stoneless?

Initial thoughts:

Airstones make pretty bubbles which is useful in aquariums but not an issue in DWC.
Running without an airstone might affect the life expectancy of the air pumps due to pressure variations?

Anyone have opinions or facts related to running stoneless in DWC?

No airstone is a good way to get root rot.

 

[Rahz]

No airstone is a good way to get root rot.

Why is that?

 

[firsttimeARE]

Would like to do this myself.

Lemme know how it works for you

 

[ttystikk]

@Rahz finally, a way I can help YOU for a change!

I've been running RDWC with no air at all for years. Turns out that waterfalls aerate and churn the water column better than bubbles. I have a water pump in my control bucket that feeds a manifold which delivers water to each tubsite. The final fitting is an elbow so I can stick it in a hole drilled in the lid of my tub. The water pours through continuously. This creates aeration, churn and circulation, so you can pitch your air stones, lines and pumps altogether. You're welcome!

Cold water to water exchange coil also sits in the control bucket.

 

[brimck325]

i believe floaming is the best way to oxygenate the water. air bubbles don't pump oxygen into the water, the surface of the water touching air does. the more you disturb the surface the more oxygen. floaming is placing a water pump in res pumping water to the surface. i haven't found much info on it, but know a few that use this method with great results.

 

[rkymtnman]

i tried the airpumps with just tubing no stones. bubbles are much larger. seemed like less restriction on the pump itself.

i'm with ttystikk and i ditched all my stones in favor of a top feed waterfall action.

 

[ttystikk]

i believe floaming is the best way to oxygenate the water. air bubbles don't pump oxygen into the water, the surface of the water touching air does. the more you disturb the surface the more oxygen. floaming is placing a water pump in res pumping water to the surface. i haven't found much info on it, but know a few that use this method with great results.

Fluming, or flooming, active water circulating at the surface. Waterfalls do this too.

'Best' is a totally unnecessary rabbit hole with aeration, because it isn't hard to maximize dissolved oxygen with any of several different methods. I chose the one I did because it was the simplest approach with the fewest moving parts/points of failure.

 

[Yodaweed]

Why is that?

If you don't have aeration the roots die, you need a water fall, or bubble stone to keep the water oxygenated. I use a water fall and air stone in my RDWC.

 

[Rahz]

If you don't have aeration the roots die, you need a water fall, or bubble stone to keep the water oxygenated. I use a water fall and air stone in my RDWC.

I'm not asking about removing the air pump, just removing the stone. I also use waterfall in conjunction with the bubblers.

What I'm asking is whether there are any tests done with and without the stone (while still using an air pump), and whether it might be bad long term for the pump to run without a stone, as I assume they're designed to run with one.

 

[Rahz]

I've been running RDWC with no air at all for years. Turns out that waterfalls aerate and churn the water column better than bubbles. I have a water pump in my control bucket that feeds a manifold which delivers water to each tubsite. The final fitting is an elbow so I can stick it in a hole drilled in the lid of my tub. The water pours through continuously. This creates aeration, churn and circulation, so you can pitch your air stones, lines and pumps altogether. You're welcome!

Nice. Do you make your own manifolds? A while back I purchased a couple. One eventually started to leak. The other worked fine but I could never adjust the valves to get equal distribution.

 

[ttystikk]

Nice. Do you make your own manifolds? A while back I purchased a couple. One eventually started to leak. The other worked fine but I could never adjust the valves to get equal distribution.

Yes, I use 1" flexible tubing and irrigation fittings. 1" x 1" x 1/2" funnypipe tees send half inch lines to the tubsites and a half inch elbow is the terminal fitting. There's enough flow through the whole system with only 6-10 tubsites that everyone gets great flow, no valves required.

 

[Yodaweed]

I'm not asking about removing the air pump, just removing the stone. I also use waterfall in conjunction with the bubblers.

What I'm asking is whether there are any tests done with and without the stone (while still using an air pump), and whether it might be bad long term for the pump to run without a stone, as I assume they're designed to run with one.

I have run without the bubble stone, the bubbles are bigger, worked ok until I got my bubble stone back (I also use it to make tea's for my organic grow)

 

[redi jedi]

Many smaller bubbles have a greater surface area compared to fewer large bubbles. More surface area = more gas exchange.

 

[blackforest]

If you are creating a waterfall to each bucket from a manifold, would the water lines all have to be the same length so it would not fill up the buckets closer to the manifold faster than the ones at the end? For example, I run all my air lines the same length and just coil up the closer ones since air like water take the path of least resistance. Or would it be pressurized so it was filling all the buckets at the same rate? I want to get rid of the air stones and just use waterfall to each bucket.

 

[ttystikk]

If you are creating a waterfall to each bucket from a manifold, would the water lines all have to be the same length so it would not fill up the buckets closer to the manifold faster than the ones at the end?

If the manifold servicing those lines is enough of a larger diameter, no. My supply manifold is 1" and the lines going to the tubsites are all 1/2".

1"x1"x1/2" funnypipe tees, connectors and assorted irrigation fittings;

 

[blackforest]

If the manifold servicing those lines is enough of a larger diameter, no. My supply manifold is 1" and the lines going to the tubsites are all 1/2".

1"x1"x1/2" funnypipe tees, connectors and assorted irrigation fittings;
View attachment 3636985

Perfect, that's what I thought. That's exactly how I built my first auto feeding system when I was growing in soil. I had a 1" pvc with 1/4" feed lines, worked great. Thanks for the pic

 

[ttystikk]

Perfect, that's what I thought. That's exactly how I built my first auto feeding system when I was growing in soil. I had a 1" pvc with 1/4" feed lines, worked great. Thanks for the pic

Mine are half inch, just to be clear. Same idea.

 

[redi jedi]

If you are creating a waterfall to each bucket from a manifold, would the water lines all have to be the same length so it would not fill up the buckets closer to the manifold faster than the ones at the end? For example, I run all my air lines the same length and just coil up the closer ones since air like water take the path of least resistance. Or would it be pressurized so it was filling all the buckets at the same rate? I want to get rid of the air stones and just use waterfall to each bucket.

Yes you would want each line to be the same length if you needed (roughly) equal flow to each site.

 

[twistedwords]

You do not need airstones in a RDWC as that was done by people who didn't know any better about dissolved oxygen in water. You could just put a pond pump in the controller bucket with a venturi attachment that comes with most pond pumps and flume it, so you get both the flume and the venturi and then use the waterfall method for the incoming water into the controller bucket. This ensures the controller is at maximum DO and the rest of the grow buckets are calm water and no need for anything but return lines to the controller bucket.