Hi, i'm new to the betta fish forums! I just had a question! I got a used but perfect with no scratches 40 gallon tank off of craigslist. (I have my betta, Mr. Nibbles, in my 10 gallon tank.) I have the tank with a glass cover. I purchased online yesterday a thermostat heater 100w, a 55/57 Oversize filter (cleaner the better!) a bunch of random fish food, a siphon for aquariums, a bunch of filter sponge thingies, black aquarium sand substrate (very fine), a 36" Fluorescent Strip Light, a giant rock with plants (silk) growing off of it, tons of more silk plants and a giant rock cave. a lot of ornaments lol. Usually I put like a small leaf in xD. Oh yeah, also I got bacteria in a bottle, its like API Quick Start water conditioner. I got normal stress plus water conditioner too. So, my main question is what kind of fish for a 40 gallon tank? its standard shape, pretty long than wide. I wanna have some nice bigger fish in it. I know oscar fish need at least 75 gals. So no, sadly... (my betta is prob going in there) I wanna have really intelligent fish, with a lot of personality, and that is fairly large (maybe like an oscar or a little less XDDDDD) I plan on getting like 4 cory cats because I got the smooth sand for that, Mr. Nibbles is hanging at the top prob, cories usually on bottom. But, I'm looking for a nice sort of large fish with personality etc. that would hang in the middle. I would prefer a colorful one. And remember, LARGE. (more than one in the middle pls, maybe schooling behaviors) Please, give me all ur opinions input etc. I am in need of ideas of fish.