My first fish in the new tank was a kaudern cardinal fish then 3 weeks later I added my gramma from the old tank and the cardinal got real shy and didn’t sit at the front of the tank anymore. I didn’t notice much aggression just some when the cardinal passed by the grammas cave. Woke up this morning to a barely alive cardinal fish with no bottom fins and wasn’t swimming. I went to set up my qt tank to transfer it then I came back up to my rock flower nem eating it. I know it was the gramma because it nips at my flame angel here and there. Is it worth removing the gramma so I can add more fish later on?