I started with two GBR(m&f). The male bullied the female pretty bad so I removed her, she later died. The male has seemed content as the only one in the tank with my rummy nose, corys and otos. But for the last couple days he’s been hiding behind/under the driftwood in the jungle Val. He was very active before even when he wasn’t chasing the female. Not sure what’s wrong with him. Any thoughts?