Thank you for the advice. I regularly check my parameters and have zero chlorine or chloramine, due to treating the water before entering the tank using complete, prime, ect... Most of my nitrates were absorbed by the plants and also some water changes. The only conclusion, I can come to at this point is seachem flourish has a lot of iron and my water here in Florida is fairly hard water, due to the lime. I lost a total of 4 grown cory doras, 4 neon tetras, 3 Dalmatian molly's. My Angels, 4 Dalmatians, 2 large bristlenoses, German Rams, and more tetras seem to have survived after (3) 50% water changes in two days. I'm going back to the API root tabs and will research Aquarium co-op fertilizers, which get high reviews.
I just can't chance Seachem Flourish anymore, which seem to work for a lot of people. However, I found quit a few people who experienced the same issue with their fish dying after using Seachem Flourish tabs. There is not enough of a buffer for error to give this product any further consideration. My fingers are crossed that I don't lose anymore fish. I feel I may be passed this, hopefully! again, thanks!