I recently setup a 10 gallon tank and put in 3 Harlequin Rasboras to start the cycle. I think two are males and the other a female. It has been almost a week since I added them and they appear to be healthy, they are active, eating, and have color. In the last couple of days I have noticed the larger male become very aggressive. At first he was only aggressive towards the female, but now to the other male also. My tank is still cycling so my chemistry is a bit off, but I have been doing 25% to 75% water changes three times a week depending on the quality. Their aren't many places for them to hide because I did not want to add plants until the cycle had completed. Does anyone have input or advice?