so is that why the arowanas dont fight in the video
It could be part of it also there are a million gold fish in there distracting them from each other. Which I do not recommend lol.
A quick heads up- I would never base any of my tank mate cohabs off of a 3-4 min video on YouTube, just because it works for the guy in the video, doesn’t always mean it will be a long term or life long situation. Especially when the fish in question are 1k plus... typically for good quality.
truth be told the size of your tank is big enough for a while but I wouldn’t even consider keeping more than one in that tank for more than a year. Two reds will turn on each other and you will end up with 2 shredded fish if you lucky. Possibly worse than that.
sorry if this isn’t the advise you were hoping for... I sharing, more research than actual hands on experience here. I have never owned reds, but have lots of friends who have. I just haven’t seen many others responding and would hate for you to lose your fish from lack of info..