New to hydroponics and noticed that my premixed nutrient solutions' PH has slowly been rising throughout the day. They're in the seedling stage so I make a solution in the morning at a 5.8 PH and slowly apply it throughout the day, but by the end the PH of the solution is usually above 6.5 (the nutrients are: FloraMicro, FloraGro, RapidRoot, and SuperThrive). Is this caused by exposure to air or light?
No, it's fairly normal for ph to increase during the day but it can also be caused by your nutes being to strong. Seedlings need no nutes till the third set of real leaves and then start real low and increase as they grow. Proper nute strength will stay quite stable in the ph dept