Using MrMalty as the calculator, for 1.048 OG, hybrid strain and 5 gallons, with a simple starter (I assume), I get 1.8 liter starter too...however it also says based on the age of the yeast you need 2 packs not one.
We are Boston Strong!
Primary - Empty
Secondary - Empty
Kegged - Peter Piper's Pail of Pumpkin
Serving: - CoCo for Coconut Porter V2, My Funny Ballantine IPA, Surly Bender AG Clone.