The warmer it is, the more they'll breed. I don't mean boil them... lol. But do watch you temps like a haek till you get the heater regulated. Low 80's, if I remember, is good breeding temp.

Er... your alfalfa sprouts are new to me. lol Let us know if they grow out of your tank and take over your neighborhood.

Current should be ok, as long as they can go hide bhind a rock or something to get out of it if they need to.