True Opinion on GPU mining Future, is buying gtx1060 beneficial in future?

hi,
i started Zcash mining with Gtx 1070, im thinking to buy Gtx 1060 one by one…
here Bitcoin mining machines got so Expensive, like s9 antminer costs 4lakhs in my city(include PSU) and it earns 900+inr per day, but if i put 10 gtx 1060 it can earn more in same power usage and less money.
but problem is if i buy gtx 1060 one by one, what can be the future of gtx 1060, would it earn half after year or 2?
i mean buying gtx 1060 means spending 25INR, would this money profit complete the investment loss in some months?
my gtx 1070 earns 110+ per day, i guess gtx 1060 earns 92+inr
so is buying this gpu profitable ? if no then what should i do?
please give some honest opinion.