Planted Tank Guru
Join Date: Jan 2010
Location: Contra Costa CA
1) Good sources of the beneficial bacteria:
Filter media from a cycled, healthy tank that is supporting plenty of fish.
Gravel from such a tank. Do not bury it in your substrate. You can scatter it over the top of your substrate, if you like the look. Otherwise keep the bacteria-rich gravel in several mesh bags and place them in an area with good water flow. You could hang them from the sides of the tank, or lay them on the bottom.
Other things from such a tank, but they have less bacteria, smaller jump-start.
Bottled bacteria, as long as it contains Nitrospira species of bacteria. Read the label, and do not waste your money on anything else.
The right bacteria will find the tank, even if you do not add anything to jump start the colony.
2) If you are planning on a high tech tank, then I would sure go pressurized. If you are planning a low tech tank then DIY/Yeast or liquid carbon (Excel or similar) is OK.
3) A 24" bulb over a 30" tank is just fine. There is enough light scattered to cover the ends of the tank.
4) Depends on the bulb, but 2 of them, spread out a bit, would cover the back and front better than a single bulb down the middle. 2 might be so bright, though, that you would have to lift the whole fixture up to make it a bit dimmer. Similarly, a really good single bulb, with a high quality reflector, set a bit higher over the tank could give you reasonable coverage.