The general rule for enchanting is this:
For maximum success rate without supplements, you need to use an enchantment stone that is : 30 levels above item level for fabled items, 40 levels above item level for eternal items and 50 levels above item level for mythical items. That means that for Bloodmark gear, you will reach the maximum enchanting chance without supplements with l105 stones, and for hyperion gear its l115 stones. This applies all the way up to +10. After +10, the success chance decreases, but you still want to use stones in the required level range.