I currently have a penguin150 for my 10 gallon tank with neon tetras, and the original output flow is way too much for my tetras.
What I did is put some java moss between the cover of bio-wheel and area where water comes out to limit the flow and that seems to work perfectly.
I am not sure how an HOB
tetra 10i looks like, but I am sure there is some way to slow down the flow.
Hope it helps.