The best way is to buy either a electric ph meter or a tester kit that comes with a test vial and a dropper to test samples and then slowly add more down or up depending on where your ph test tells you. Everyone's water is different so there isnt always a set ratio that covers everyone.
As for the nutrient refer to the feeding suggestion on the bottle or on the companies website start off at half the suggested dose and then work your way up slowly. Always make sure to add nutes to your water first then ph balance before watering your plants.
alright thanks man, i just have the ph tester where you read from a chart. and another question on the nutes when would it be the best time to start giving it to the plants, and do you switch off watering them with the nutes then to fresh water or just give them it the nutes the whole time.
Everyones different, I try to feed every 3rd or 4th watering but I know plenty of people that feed eveery watering... You just gotta get to know your plants and what keeps them happy, stay high!!