Yes, I would test the water daily for ammonia and nitrites and do water changes.
If you can get your hands on some establish BB from another tank like suggested that would help.
Another option would be to get some BB in a bottle (I think Seachem has Stability) and see if that will help out.
The best thing would have been to keep the old tank set up and move over a small amount of fish at first, like maybe a pleco. That way you wouldn't have "shocked" the tank with too many fish at once. Doing that would have allowed you to slowly introduce more fish over an extended period of time (few months).
Good Luck.
If you can get your hands on some establish BB from another tank like suggested that would help.
Another option would be to get some BB in a bottle (I think Seachem has Stability) and see if that will help out.
The best thing would have been to keep the old tank set up and move over a small amount of fish at first, like maybe a pleco. That way you wouldn't have "shocked" the tank with too many fish at once. Doing that would have allowed you to slowly introduce more fish over an extended period of time (few months).
Good Luck.