Why is he so small?

[200xth]

When he was around 60 grams...I was feeding him 10-15 gram hoppers at this time.

Most of mine hatch out slightly bigger than that, but I do the same thing. Mouse hoppers twice a week until they are around 90g to 100g.

I switch them to once a week at 100g but other than that from what I saw, your feeding is very similar to mine as far as size and weight go.