I bought 2 German blues about a 5 days ago.
Beautiful fish that have acclimated to the tank and tankmates wonderfully! But I've noticed the female's black coloration will become pale at times and return to normal at others, sometimes quick enough for me to see the change. she's eating fine (mix of flake in the morning and brine shrimp at night) and doesn't look sickly at all.
The male causing this is my best guess. He'll chase her down so he can display and bugs her often to do so. Other than that they get along fine! None of the other fish ever bother them. They swim all around the tank now instead of just staying in one corner and behind the plants.
The male never hurts her from what I've seen, just chases and displays. They do get along often but mostly he wants to display.
Will this be harmful to the female?