if i were to use one of the things you listed. would i just use one of them for my entire substrate or should i layer it? sorry i'm new to this and was trying to search, but i didn't really see questions that were a 'substrate 101 for idiots/beginners' lol.
just want to know what to buy when i go to the LFS this weekend. i dont think i want sand because it might get sucked up into my filter. preferably something that is black/white gravel-ish. don't know what layers to use
It's not necessary to layer your substrate unless its for a reason. For example, some use soil or peat underneath their top layer, but you need the gravel to keep the soil weighted down, or keep the peat from having full access to the water column. If you are using something like eco complete, or aqua soil, this isnt necessary.
If you are looking to purchase from a LFS only, your choices will be limited to either sand, gravel, fluorite or eco complete. I highly doubt you will find an LFS that will carry any great premium substrates. Of course, thats not to say eco complete sucks, its just far from complete.
Like mentioned earlier, you must take live stock into consideration. Some fish like more acidic water, while others more basic. Your choice on substrate will depend a lot on this. Though, most beginner fish will do fine in either, as long as its stable. However, fish like corys who dwell the bottom would appreciate a "softer" substrate as to not damage their barbells or bellies.
Then, think about your plants. Even in a low tech setup, if you use an inert substrate like gravel or sand, you will need to dose ferts and use root tabs to not kill your plants. You can get away with less fertilization with no CO2 and a better substrate, but you may have to play an active role in monitoring any deficiencies that may crop up.
Personally, I hate sand. Its hard to clean and gets disturbed very easy. If you are only going for LFS products, and they don't have aqua soil or fluval stratum, I'd go for fluorite.