In regards to food, I placed frozen blood worms on the bottom of the tank with tweezers and observed them eating with no issues in both tanks. They have basically been hand fed blood worms since I got them. They don't tend to go after the blood worms per say, but if the cory's swim over the blood worms they will stop and gobble them up. Now that they are in the top tank, I try to put the blood worms on the catappa leaves just to make sure it's easy for them. There is no doubt that stress has played a key roll in this, and I have been testing pH all week via API. I have not noticed any fluctuation, but it's always a possibility. I can lower temp and nitrate for sure. I do 50% usually, so I can change more when I change water next. I dosed with easy green on Monday, and have been feeding heavier this week, so nitrates are rising faster than normal. You can see my java fern "garden" in the top tank where I grow out plant-lets.
I got them from a different store this time.