You need bigger hose. The blackice uses 3/8 inch and the Ehiem is 1/2. I'm surprised any place would give you less then 3/8. Thats usally the min size.
Since the fittings don't match, you'll need to either get strechy tubing (thats what I did, use Silicone based tube in this case) or get a reduces fitting to convert the 1/2 inch portions to 3/8 inch.
Check
www.dangerden.com or your local hardware store.