The tank is filtered with an undergravel, very well aerated. Let me add
that this tank is on my desk in an office. During the daytime hours it is
lighted (hooded light). When I leave the office the tank, at night, is in
the dark and they turn the heat down, it may get as cold as 62. The tank
has daylight over the weekends. I could certainly do 2-3 male guppies. I
can try to find the White Clouds as well. Last fish was a betta but I hate
the idea of a fish by itself (maybe that's just a female thing LOL).