poland spring water and happy frog soil

Hi all quick question - problem.

So I started a few seeds recently and transplanted a clone I had at the sane time into happy frog soil. The clone has been doing great so far and the seedlings are about a week old. My problem is stupid me didn't check the ph of this bottled water I bought until today and its ph was 7.5. My clone is about 1.5 ft now I just lstd it about three or four days ago and since a few days before that its been showin rusts signs and slight yellowing of the leaves ( I know pics would help they'll be up tomorrow!! As soon as I can get a camera other than my phone) since about when I transplanted then. But the problem is I started using the Poland spring water(switched from bottled distilled because our local Walmart ran out) at the same time as when o transplanted into the happy frog. Now I've watered the seedlings with the water about three times now is it ok to flush the seedlings or should I just get distilled water again and ph it to normal and water from there? And does anyone have any input on happy frog soil?? Please ans thanks for the help guys sorry about the book up there ill bake you cookies if you help

Use organic nutes and a little lime and don't worry about ph. Plus Poland Springs water gets expensive when your plants get going. GO line and teas! Don't flush!

Yeah I have a ro system I got from htg I'm just trying to figure stuff out with the reservoir I'm gonna have buuut nothing a little reading can't solve. But Thanks I've read alot about dolomite lime but never really very far into it. Now should i check my soils ph run off and add lime accordingly or? And for nutes I have fox farm trio from last grow and i just picked up dynamic grow grow and bloom with pro tekt I'm pbly gonna be tryna the dg on half and the ft on the other half. An experiment.. an evvvillll experiment mwahahaha.
Ohh I love that first hit of the day haha sorry about my wakiness