I have a new 75 gallon tank, I have a few questions. First peaceful community tank? Pearl Guaramis, Cory catfish, and some live bearers? Or aggressive? Jack Dempseys, Green terrors? a mix? I just cant decide. Also has anyone ever used glass vases as a stacked cave? I have hundreds of big and small jars and vases of cobalt blue glass, could they be siliconed together to make a big cave pile? Would it be too unnatural for the fish to be comfortable? Any advice on stocking welcome! Also Im looking into getting a sun sun HW-402B canister filter with UV sterilizer alleged 264gph, has anyone used this? Is there a better filter I should use?