Thanks for writing in.
The symptoms you are describing can be due to androgenetic alopecia.
It is a hormonal condition.
It has nothing to do with filtered water.
The treatment can be minoxidil
You can use tablet follihair
and minoxidil safely.When used properly minoxidil is very safe and effective.
Follihair is a biotin preparation it is very safe and you can take it for 3-6 months.It strengthens the hair and prevents hair fall.
I encourage you to visit a dermatologist
for proper diagnosis and treatment.
Hope this helps.