Please keep in mind that all advice given here is free of charge, and it is up to the OP to take or leave that advice.
We are here to help, not to disrespect. The advice given is in the best interest for the well-being of our fish, and the peace of mind for the fishkeeper.
The most important factor to consider for the health of our fish is the water parameters (conditions) our fish are living with in our tanks...specifically, ammonia, nitrIte, and nitrAte levels in the water. First and foremost, we need to know these levels before considering other factors that may be contributing to detrimental behavior or health of our fish.
Again: How long has the tank been set up?
What kind of cycle did you perform, fishless or fish-in?
What kind of test kit do you use?
What are your readings for ammonia, nitrIte, and nitrAte?