I actually answered your other thread. I echo keep stable water parameters and not adding salt. Most importantly get a report on your local water service's parameters...it should be available...moreover, test your tap water. Take most LFS employees statements with a grain of salt; however, there are some LFS owners that are a wealth of knowledge. Most of the time they are trying to sell the dry goods on their shelves...it's a business.
Most people start with Mbuna. Go with a single dwarf Mbuna species (highly aggressive) in a 36" tank, a pretty decent amount of rockwork ( get river rock from a landscaping, or stone place). You could always get yellow labs or Saulosi (you could try two species, but your going to need a > 1m/3-4f ratio either way). My vote would probably be Saulosi. Real estate (tank footprint) is also a big factor being a 36" length. As stated, Mbuna are nasty little buggers so expect hyper-aggressive fish, warfare, and deaths until the colony stabilizes. D/t the rockwork with Mbuna, it can be cumbersome to remove the hyper-aggressive fish sometimes...or fry for that matter.
PS. Don't worry you will soon graduate from Mbuna in no time...then get a 4 footer and try peacocks, then Haps, then a group of Tropheus. Then most likely you will dive into SW and find its a PITA in the long run, & then get a 6 foot tank and try various setups. This is only the beginning. Watch out for Aqua-Piscis Neurosis or Multiple-Tank Syndrome. I hear it can be pretty absurd at times. Enjoy!