Airstone/Airpump question

Got my plant running DWC/Drip with 2 air pumps no more than 4psi each running 12 inch airstones in 30 litres of water. its my first time trying DWC and i dont know if im producing enough oxygen for the plant, i have both airstones directly under my one plant since i got only 1.

is that enough for my one plant?
should i get a couple more for my res. is it enough?
and how many would i need for 4 plants...

jesus son. got a little bubble bath there huh? You have plenty of oxygen. Take it from me, I use one 10 dollar pump on one 18 gallon rubbermaid resevoir and it's plenty of oxygen for the plants.. I can't believe you're actually using two pumps for one res, that's just crazy.. you got more than enough. Maybe that's a good thing though, since you're drippin, which is unnecessary imo.

How about in DWC grow.....would there be an ideal amount of bubbles or the more the better??

ok I know I didn't specify this, but I DO a DWC grow. I use one cheap ass pump for each resevoir. This provides PLENTY of oxygen to the water (thus, the roots of your plants). Basically, as long as you have a pump that can blow air through a hose into an airstone and make bubbles in your water, you have accomplished having enough oxygen in your water for the plants to thrive. I know people can't get their minds around this, neither could I really.. I don't see how, but the fact is, it literally just works. It does not need to be a fuckin jacuzzi, just bubbles! If it bubbles it's good!

side note: soak airstones in water for an hour before using.