Thoughts on the 2L-DWC-H:
The pros: For me, it was much easier to maintain/upkeep than the DWC I started with. Of course, this was my first attempt at any grow, so going DWC may have been above my pay grade given the pH battles I fought. In the 2L's the res is empty daily so it gets the right pH water daily.
Easy to move the plants around if need be. The small container size (and empty when they're thirsty) was easy, and for some who are doing sogs, you don't even move them. Much easier than moving a 3 or 5 gal pot full o dirt.
No transplanting, no shock. They lived their whole life in one container, so never went through the kind of transplant shock that can happen.
Re-usable: I'm running the same 2L's still in my new grow, as soon as I pull one from flower, it gets washed and put back in to use, easy.
Cheap! can you say free for dumpster divers? Every recycling center has boatloads of these for an unlimited supply.
Enviro friendly! You're helping the planet by re-using someone elses "waste" that would have required energy to recycle back into a park bench or fuel or whatever.
Decent yeild I was quite happy to end up with 3 zips off my first try at this off of basically four main plants. I'm not counting the weights of the autos or bubblegums because they were basically nothing relatively, and not even in my final totals.
Cons:
They tip over. Once they get to a certain size in flower, they get top heavy since they drink the res, and can easily tip over. I ended up setting up a gorilla tape trellis to keep them in line.
Res maybe too small If you're doing a sog with a bunch of these packed together, you'll probably be fine, but I vegged them much longer and they ended up drinking the whole res quickly as opposed to having to water every other day as others reported. Even when I moved the hempy hole higher, they still drank it all. I have a new set of 2.5 L's that are square with more volume available for the res so we'll see how those go. I'm also looking at 1gal containers.
I don't really have that many complaints about these, but have little to compare them with. I'll re-review this once I have another grow or two under my belt with this and other methods.
All in all, it was a great way for me to get my feet wet in hydro or growing in general, and if you've got a little corner in your space (which no one has) that you need to fill, it does the job cheaply.
Other notes:
I definitely see a large difference with an airstone. I used the hydro store ones and cheap big box ones and ended up liking the smaller, cheaper ones since the res is so small, and since there are so many of them running.
Green 2L's seem to have less res issues I had read this somewhere, but it ended up being the case for me too. Not sure why, but the roots seemed to like it.
Ice baths only in veg I gave myself a bud rot issue by having these sit in icebaths during the whole flower cycle. Now that I stopped my RH is 43%-70% instead of up to 90%.
Thanks everyone! This would not have been possible without you!
Well I knew who I was writing, But I had a Brain Fart. Anyways SB, I meant every word I said,Damn I feel FOOLISH!!!
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Take Care SB. SINCERELY, BOBTHEGREEN, LOL!!!
I remember when I quit burning for a while, my first time back to 
I took a 
had a huge 
was like, woah!
then I felt like this guy
but eventually mellowed out into
I am bushed, Posting Pictures ASAP. SINCERELY, JAMESTHEGREEN.
SINCERELY, JAMESTHEGREEN.