walmart...5$ ph test kit in the fish section....it comes with a little test tube, you fill it to the line and add 3 drops of solution that comes with it and the water changes color...match the color to the chart that comes with it and your done. one of my best purchaces for my grow. i had probe one and it was garbage. lemon juice for ph down is like $0.79

Walmart.com: Freshwater Master Test Kit: Fish

this is the fancy one, they do not sell the one i am talking about online i guess but you can get the idea from this.
bluntar Reviewed by bluntar on . help reading PH of nute water im using a ph control kit from general hydroponics. when i add nutrients to the water it turns a dark brown and its hard to get an accurate reading. its also very difficult when i try to measure the ph of my plants runoff. dont have the money to buy an electric meter and i hear theyre not all that great anyway so i was hoping there would be another solution to my problem. Thanks to anyone that can help me:jointsmile: Rating: 5