Welcome back fixit!!! Hope your doin better. But SouthDown Tropical play sand (and yes the tropical makes a huge differance), is a type of well play sand sold from Home Depots, but only on the east coast, that is very very cheap like $3 for 50 lbs of it. It is aquarium safe, it is harvested of the coast of Bimini in the Bahamas, and has been sterilized, a downfall is that it is very very fine, and will cloud up your tank if you dont give it a good rinse 1 time.
But thats basically what I did, I bought 150 lbs of SD that I had to order from Pennsylvinia (shipping was terrible, but still paid less than 20 cents per lb), and then added 40 lbs of ls to the tank, so far so good, but it still is pretty early to tell. That's probally the best way to seed it, but lr also helps the seeding process, so will a det kit, but they can be kinda hard to find.
-Mark