Adjusting ph

[BlwnDroOn24s]

I am in a pinch and need to lower ph immediately and have no access to ph down until tomorrow. I read that vinegar can be used to lower the ph but I don't know how much I will need. I need to lower the ph of the water in my 20 gallon hydro setup

 

[guttokill]

baking soda?

 

[MadameCrash]

It's impossible to say exactly without knowing the PH of the water your starting with and how "hard" it is. Do you have a meter?

Peace
MC