I must have the most aggressive of aggressive. So i had the divided ten gallon going for two weeks. I even cut a plastic folder to size and poked holes in it. Small holes. And put it over the transparent divider. Nope, it didn't stop my two guys from flaring their gills and egos. They would sit where the divider meets the glass for hours and hours. Yet they could hardly see each other! So, i separated them in their own tanks. Again! Oh, my clear transparent white one, has started changing to blue, purple. I will get pics up soon. Hope you all are doing well.