consumption of 35 mg/l KH in 24 hours - normal?

[Chin_Lee]

I've been trying to determine how much Alk my system uses so I stopped my Calcium reactor and began to dose with homemade two part additive with Calcium Chloride and baking soda.
I had dosed overnight with the additives and yesterday I tested at 9am and the alk results were 160 mg/l (8.96 dkh).
34 hours later, the results were 110 mg/l (6.1 dkh)

If my calculations were correct, thats about 1.47 mg/l that my system is sucking up per hour or about 35 mg/l per day. My tank is heavily stocked with mainly acros, 3 clams, as well as LPS.

I'm just wondering if this is considered normal for anybody else who uses two-part additives.