Aeration - more than Dissolved Oxygen levels?

[Cory Torrella]

Aside from keeping the DO optimal for fish and plants, has anyone placed direct aeration under the physical plants and compared growth with those without? In a little experiment, I noticed a visible, positive difference in growth speed. Would agitation be a factor, stimulating the roots?

[matthew ferrell]

You should see better results with small bubble, not larger.  This has to do with surface area.  Small bubble surface area>large bubble if volume is head constant.  It is the surface of the bubble where diffusion takes place.

Harold Sukhbir said:

Hi All,

In my small raft i compared grow out time with and without added aeration. From visual observation I estimate between a 20-30% increase in plant size over the same period( this is not weight of plant) using air. By increasing the pore size of the stones i see a sightly better conversion time for nitrification. Do you have the same results?

[matthew ferrell]

Remember all, if plumbed into the same system the shallowest air stone will release the most volume of air.  It is best to try and get all stone in the system to the same depth.

[TCLynx]

And if you can't do that, you then have to put valves everywhere to try to balance it.  Really difficult in a sprawling system where you won't be able to see the flow from all the air stones from each valve.

matthew ferrell said:

Remember all, if plumbed into the same system the shallowest air stone will release the most volume of air.  It is best to try and get all stone in the system to the same depth.

[matthew ferrell]

Even with valves, every time you open one it changes the rest.  It is easier(and less frustrating) to have the forethought of where do I really need the air stone to sit?

[Ryan Chatterson]

True but you will still deal with differences in air flow rates because of friction loss through the length of the pipe (1st stone has less resistance then the furthest. I always use valves and as long as you don't hit the adjustment handles they work great. Also clean all your stones at the same time so the resistance through the stones isnt different.