So you have a 225g right, thats a big enough tank for bichirs, what you could do is adding more bichirs in, endli or ornates all up to you to reduce the aggressor or your bichirs. Did you also mentioned gravels in your tank?its not save to use them, sands or barebottom tank are better.
I used to put hiding places in my 200g tank, and my bichirs used to fight for it. I then removed those hiding spot and end up with bare bottom tank which looks better and easier for me to clean their wastes.
I used to put hiding places in my 200g tank, and my bichirs used to fight for it. I then removed those hiding spot and end up with bare bottom tank which looks better and easier for me to clean their wastes.