I've actually contemplated that quite a bit. I've talked with TTY in depth about it and even came up with a version of it myself in one of those threads. And it would be far cheaper.
BUT---- I don't want to be testing anything on myself (at this stage of the game). Until testing has been done with proof of harvest equality compared to the same system with proper air AND until I have figured out myself how to dial everything in, I will stick to with what's proven.
And that's not meant as a dig at anyone--- not in the slightest. I just new to 'toe the line' until I grow some wings;)
The Captn on another forum has conducted oxygen sat levels using every method currently being used with some very accurate measuring equipment and his results PROVED that flooming and waterfalls produce the least amount of DO available to plants. I would love to see all of these type of myths debunked as it diminishes the advancement of any real innovation towards the actual science of growing. We are not in the dark ages anymore and therefore there should be no need to keep guessing like this is alchemy when there are so many proven methods backed up by hard facts. The amount of bad info being passed off as science is off the charts when it comes to these cultivation forums.
All the stones that you have listed have a track record for being a poor choice in DWC. The sweetwater will crumble apart and clog within the first 3 weeks. The Oxy Shield will gum up and at the same time not offer even distribution of air as well as root shear. And porous PVC is too expensive and requires a high PSI rating on your air pump to be effective. Also it cannot be cleaned. So far the only stones I have seen worth the $ are the Alita Sintered stones. The are able to be cleaned over and over again, they are hard and self weighted, they have multiple connection ability, they come in various lengths to accommodate various modular situations, and they are not terribly expensive.
