[davemonkey]

Clayton,
any substrate/gravel you want to use is fine. There is no need to by specialty products, many people on this forum use plain sand, or soil from their yards topped off with gravel, inert fired-clay, etc...

I would caution against using large gravel (get the smallest pebble-size you can find) because it tends to 'muck-up' in my experience. Also, plant roots have an easier time in finer textures.

If you start off with very low light (and plants that will tolerate it) you won't need any added fertilizers (I say that with some reservation) . Keep in mind that flourish alone only provides micronutrients and not N,P,K (macros) .

You might want to spend some time reading throught the El Natural area. That may be a great place for you to start if you want to save money on lighting (use natural sunlight) and ferts (soil and fish food/excrement provide all you need) .

Also, look at the gold menu-bar at the top of your page and go to the Library and find AaronTalbot's mineralized soil article. I have tried this (a modified version) with success. I found it's not necessary to wet and dry the soil repeatedly if you use soil from the yard (it's already weathered) , but you have to be careful that you aren't introducing harmful chemicals into the tank.

-Dave