A heater will be mandatory, unless you live in a permanently warm climate. This is one piece of equipment where it pays to buy the best. A heater that fails, whether it overheats or stops heating, can kill a tank of fish overnight. For a 30g I would suggest a 150w heater minimum, or a 200w heater. There are good brands and there are some quite unreliable brands. I got on the bandwagon of the new Fluval digital heaters a while back and got 3 of them, and one has already failed. And they are not cheap.
I have never had trouble with my Tronic heaters (running for more than 12 years now), and my recently-acquired Eheim Jager seems well made (as one would expect from Eheim). Other members may have suggestions for good reliable heaters beyond the two I've mentioned.
Lighting somewhat depends upon whether or not you intend live plants. Many of us will strongly recommend plants, their benefits cannot be understated, and they are not difficult; but good light is critical. I have a 30g (29g actually) that is the standard 30-inch length, but you mention a 30g tall, so if you could give the dimensions (length, width, height) I could suggest some lighting.
When it comes to fish, we have profiles under the second tab from the left in the blue bar across the top of the page. Water parameters of the source water, presumably tap water, are important as some fish need harder water than others, and some need soft water, while others manage in between. You can ascertain your tap water parameters from the water supply folks; many now have websites with data posted. The hardness, both GH |(general) and KH (carbonate or Alkalinity) is important to know [these usually won't change in the tank unless you target them somehow], plus the pH which is linked to the afore-mentioned. Numbers for shoaling fish (that need groups) and minimum tank sizes will also appear in the profiles.