Flush rockwool is it necessary?

I am about to transfer some seeds to rockwool and I know about soaking and adjusting the Ph but I read that after that you must flush with distilled/spring water I just found out that my tap waters Ph is over 7.6 and that`s bad I know so I plan on buying a Brita or bottled water till I reasarch Ph down options....and after they need water to give them 1 quarter dose of 10-15-10......baby food they called it and warned not to give them plain water.....any opinoins or comments appreciated!! Cheers

I've been using rockwool for years and you do have to control your ph. Rockwool tends to raise the ph constantly during the whole grow period. I keep my water and nutes at 6.0ph.