First I actually carry excess water to add weight(and I feel this is the smartest way to do it in Fl) and I have it distributed in bottles between easily accessed in rear pockets to relatively easy access in pockets on rear of bike to packed away on rear of bike (ie harder to access for emergency).However if I was trying to minimize weight here are some tricks I'd try.First if I went with a camelback I'd go with a small size to get weight off my back and because in hot weather you will tend to drink the water too fast if it is that easily accessable and run out too soon.I would subliment that with a bottle or two less accessible in case I ran out.But the real key is to try to drink the water evenly and sparingly until you get to a refill source and then at that time splurge and drink all you can and then top off the supplies before you leave.