My betta has been in the 10 gallon tank with the harlequins for 6 days now. I've noticed him chasing them around more often, and I'm a little worried that one day he'll actually eat one! Of course the harlequins are much faster, but I can't help but wonder if he's just being a betta fish or if his aggression is getting worse. I can't tell? The harlequins still look healthy and I just hope they're not living in fear.
My betta has gotten way more comfortable in the new tank and seems to have claimed the left side of the tank where the harlequins like to play and mate. So I went out and bought 2 anubias plants for the harlequins new area, hopefully this will give them more hiding spots and feel safe again.