Ok I'm back, man Rocky your Bichirs looking great! He looks so happy and he's grown a ton! Ok here's my list:
1.) Columbian Tetra: These are rather large, awesome looking Tetras that will add tons of color and movement. They're honestly pretty friggin awesome looking fish when in a big school (7+ is a recommended number). With your stock id say the most you could safely get is 12.
2.) Penguin Tetra: yet another awesome Tetra, my personal favorite these guys will add lots of movement to your top strata. What they lack in color they make up for it in size coming in at about 4"! I love these guys and personally I would get these. No more than 12 to not set you over.
3.) Black Ruby Barb: I love these guys and their color when happy and comfortable is breathtaking, nothing compared to their breeding dress though! Normal I wouldn't recommend a smaller Barb but their odd shape and speed should keep them safe. I'd be cautious if you do get these (with your stock id personally do the other two choices) because the Leopard Ctenopoma, and in rare cases the Bichir too, may take a likin to them. Like me when I see a steak.
Rocky, since none of your fish are small fish if any of those fish become Bichir food you need to let me know so I can call the air force and carpet bomb him. The Seneglaus Bichirs are not known to be overly predatory and are instead known for their more peaceful and laid back temper of the Polypteridae.
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