I just moved my young oscar Marlowe into a 65gal tank with a young Firemouth (Cal). It's a sort of growout/get-to-know-you tank (here's a different question, would a Jack Dempsey and a Convict fit to growout once they are about the same size as the Firemouth? Or should I wait until I have my final tank, a 150, to put them all together to see how they do? I've picked the species based on several suggestions, and plan to switch them out if need be)). They seem to play nice, as in they swim near each other, sometimes one follows the other, but there's no chasing, and they only seem to hide from me, or each other when they move too quickly and startle each other. Their tank is a bare bottom, which I don't know if I should keep... I personally like the look of substrate, and I would think that the tank would benefit from as many bacteria colonies as it could get.
So should I bother with a substrate? Would gravel or sand be better for these two? How many pounds do you think, for this size of a tank? Also, my oscar is often dark, he only shows his slightly lighter colors (just some cream-ish patterns on a dark body; there's only a drop of orange at his gills and his tail) when he's trying to get my attention to feed him, or a day or two after a water change. Would lighter substrate be better, or would he flash more against a dark one? Is it purely personal preference?
So should I bother with a substrate? Would gravel or sand be better for these two? How many pounds do you think, for this size of a tank? Also, my oscar is often dark, he only shows his slightly lighter colors (just some cream-ish patterns on a dark body; there's only a drop of orange at his gills and his tail) when he's trying to get my attention to feed him, or a day or two after a water change. Would lighter substrate be better, or would he flash more against a dark one? Is it purely personal preference?
