SO I finally redid my over grow grass tank. When I did this I took out ever single plant in the tank. After that i was sad to see I only had 4 of my original 14 scwhartzi cories left. So I went and bought some julli cories. I did this 3 days ago. Today, I woke upo and what was sitting theree at ther front of my tank. All my 14 + 5 cories. an they turn invisible? where did they go?