River rock or washed gravel is a lot harder to walk in compared to 2-4" limestone. The gravel wants to roll when you step on it especially on a slope. The limestone will also very slowly add some lime to the water; not a lot but measurable. The pros of gravel is it usually grows less algae on it compared to lime stone. Lime stone especially the lighter colored softer types, leaches calcium carbonate and some phosphoric acid, both used by algae for growth.
As usual there are pros and cons.
Last edited by Bill Cody; 03/27/14 02:01 PM.
