unless it's a brand new Ultralight, you should be fine; if it is a brand new Ultralight- you can test it at home, that's what I did with my second one- treat 10-15 liters and you'll know if it works as it's supposed or not
I always bring Aquatabs or MicroPur tabs as a backup- that's using a Steripen OR a filter, it's with the 0.1 oz of weight
