A varied diet is best. Mine are a bit larger and eat anything including chopped muscles, whitebait, prawns, bloodworm, flakes, catfish pellets, floating carnivore sticks, cucumbers and any other veg. They truly are omnivores and eat anything that goes in the tank.
I would prefer to put them in at least a 6x2x2 although other people on here would possibly say that they could be kept in smaller tanks. They like to be able to stretch their fins and therefore they need a tank that allows them to be able to do this.
They are peaceful fish and can be keep with fish or similar size/shape with no problems. Ours are with chalceus, limas, plecs, cigar sharks, bush fish, catfish - see my profile and they are fine.
I say say guess so on the angels and gouramis and no idea on the acaras. Hopefully someone else will be able to say yes/no to these fish.
They probably have enough room at the moment, so just as and when you feel like it. If you find the tank and you have the space and money to set it then you may as well. Lets face it we all like having more space.
i always heard most of those sharks like that like small live foods, like adult brine shrimp, and white worms, and pretty much any live food they can chase. not for sure, but atleast thats what i've heard. sorry i wasn't much help...
Oh ok i think my friend said that a fully grown silver shark could take down a fully grown male betta but if they dont then ok.
would frozen or live food be best to feed them on?
thanks for all your help