In general, you'll get better yeast growth from a starter in the 1.020-1.035 range. The easiest way to achive that is to use .75 oz. DME (by weight) for each cup of water in the starter. You're not in serious trouble this time, but try to get that gravity down next time.
An even easier way is to go metric. 1 gram of DME for every 10 mL of water gets you right around 1.035.
Maybe on the other side of the pond, as that's what they grew up with. I guess I'm just old school...