I have had a pair of german blue rams in a 40 gallon for almost a year now. They spawn about every two weeks, although they suck as parents and the eggs/occasional fry get eaten by other fish or the GBR themselves. About a month ago my male has turned really aggressive towards my female during the periods when they are not spawning. She is getting pretty much constantly chased around the tank whenever the lights are on. She has lost a lot of color and is definitely stressed from this behavior. His agression is pretty much limited to his mate, and other than spawning periods shows no agression towards the rest of the tank inhabitants. They are continuing to spawn together though. There have been no changes in the tank either in inhabitants or scape during this period. Water quality looks good. Any idea what is going on here? Is my only choice to stop this behavior is to separate them?