Hey all. New here but I've been keeping fish for over 10 years. Started Africans a year ago.
Just a thought for the OP. If you havne't noticed anything like stress from other fish, water conditions, etc I would check your heater.
I've read of stealth heaters throwing current into the water and can drive fish "crazy". I read of one fish ramming into rocks. See if you can get ahold of a meter to check your tank for stray volts. Sometimes you won't even feel it when you put in your hand into the water. In one case one heater was throwing about 35 watts into the water....that was the fish that threw himself into the rocks. Just something to check into if you're still seeing odd behavior. Unfortunatley I own of these heaters myself. I'll look at replacing it w/an Ebo Jager maybe....Going to do some more reading on heaters first.
Cheers,
Kj