I'm in too for salsa! Where you @ Sota? West Coast?
So when you're cloning do your stems sit in the water? If so I'd drop that water level a bit. What you want is a fine mist from the bubbles popping spraying your stem. That gives it enough to stay alive but it knows it's gotta grow some roots to get some more water. Experiment with the level a bit, I'd estimate a half inch to a full inch. If you look at mine you'll see that it's about an inch sometimes two between the water level and the bottoms of the netpots. Once the roots emerge, they can do whatever they want, but up until then they're workin for it!
You said you're gonna go mass cloning (like 20) right? Instead of making another bigger single res, you should make a couple more shoebox ones and put like 6 in each and then do one with the stems in the water, one with the water level an inch below the stems, and one with it two inches below. We could see what the best technique is and then all your eggs aren't in 1 basket. I think the water level is your issue with your cloning, my 2 cents though.