making sure i've got the basics down

[nchips]

ok - if you're curious about why someone who knows nothing about fish got a fish, please see the bathtub thread :)

i've got a convict (are there different kinds of convicts?). he's between 3 and 4 inches long. he is basically all grey, with darker grey stripes - and SOMETIMES i see the faintest tinge of metallic green on his sides.

he's in a 15 gallon tank now (big enough, yes?). he (i was told he's a he!) mostly spends his time in one corner, or in the hiding place i made for him. he's got gravel, a couple of plants, and a filter (looks like this, but not exactly the same one: http://www.petsmart.com/global/product_detail.jsp?PRODUCT%3C%3Eprd_id=84552444180 8569&FOLDER%3C%3Efolder_id=2534374302030059&ASSORTMENT%3C%3East_id=2534374302023693&bmUID=1141276152218&itemNo=24&Nao=24&In=Fish&N=2030059&Ne=2 )

he doesn't have a light, or a heater. important?

[ROLLIN]

If yours turns out to be a big one he will need a bigger aquarium. I would personally be looking for a bigger aquarium anyway, I like to give my fish some room to stretch their fins. A light is not important unless you want it for your viewing pleasure or you want live plants (which a convict would likely destroy). A heater may be necessary. If the temperature doesn't stay at least 70 on it's own or if you notice alot of fluctuation, I would get a heater.