If you wanted to save some money you could get some pfs (pool filter sand). It's one of the best freshwater substrates, imo. I have it in my 55g african cichlid tank and I didn't even use all 50 lbs and they love it lol. I also have it in my 2.5g biotope tank and its doing fine. Also 50 lbs is usually between $1.99 (at my friends meijer) and $15 (at my local pool store lol).