either way as long as its 2 years at least...then im golden, i do plan on feeding well and keeping them nice, fat and happy...I picked up some random river style stones, there kinda ghetto though and most arent really smooth and round, so im going to pick through them for some nicer ones...being winter there isnt a lot of supply for any garden work, i may have to just go with black sand...i can get tons of small river rocks from the dollar store for like $1 for a pound of 1/2-1'' pieces, might be cheaper to just get 2 bags of black sand...