I hate to say it, but if you can't afford ph down 7-8 bucks...how can you buy that other wierd stuff?

If you can't afford 3-part and ph down...You need to forget about hydro!!!

Go get some pots and some decent soil w nutes and go from there.

You can't just change from Pro nutes to some miracle grow and expect anything but problems. Imho, Sorry for your misfortune.lw

Also; If adding vinegar causes your rez to foam, then you have water issues to deal with.