Been messing about with a hybrid venturi/vortex aeration system for RDWC, for a number of reasons
Keep in mind this is just a ‘proof of concept’ and not something I would put into use as you see it.
It consists of the tub container (rez) with a 4000 l/ph 30w submersible pump at the bottom. It pumps up through the venturi fitting at the top side of the bucket which is offset so that it creates rotation. The bucket has a 1.5 cm hole in the centre bottom that drains back into the reservoir via a ‘vortex’ or whirlpool.
The clear tube you can see running to the venturi just lets you elevate the air intake so if the venturi becomes immersed it will still suck air in.
As the water passes through the venturi it pulls air in from the tube and feeds the aerated stream in, driving a whirlpool in the process, if you tune the outlet and/or the drain hole then it is possible to get it so that the vortex collapses just prior to going down the drain hole. This is best for aeration.
Some benefits are:
Easy to scale up and can be added into the reticulation loop of an RDWC setup, for small setups air pumps are all great, but when it’s dozens etc it becomes a PITA. Other than the pump there is nothing here to go wrong.
No air stones required. So no more cleaning, replacing air stones or buying expensive scintered silicon dioxide stones so you can get more than a few grows before they dissolve.
Less noise. It requires a some tuning but this system is virtually silent.
In theory both veturi and vortex aeration are more efficient than air stones, although I don’t have a dissolved oxygen meter to test, the combination of verturi and vortex should be more efficient again.