ph level? for cloning help???

ok i made my own aerocloner last year and it worked great 6 out of 7 was my succesful rate, but this year i cant even get 1 to root just strait tap water same as last year.what ph level shud i keep my clones for them to root +rep

I shoot for 6.3-6.5 and that works well for me.

use 5.5 to 5.8 ph b