So you're mixing a nutrient solution and you add your pH adjuster and you notice a milky white swirl appear in your reservoir. What's going on? Sometimes when we pour a concentrated pH adjuster into our nutrient solution as it goes into the water and is moving around in its concentrated form it actually starts to bind with some of the nutrients in your solution into forms that are no longer available for nutrient uptake by your plant. So this is what people refer to as nutrient lockout. Essentially the nutrient is binding up into forms that are no longer available. How can you deal with this? If you know how much pH adjuster you need to add to a given reservoir you could add it before you add your nutrients so your pH adjuster is diluted fully without throughout your nutrient solution and then therefore no longer available in concentrated forms to bind up with anything. Another way to go about it if you want to add it after you've added your nutrients is to dilute the pH adjuster heavily before you add it to your reservoir. So there's definitely ways to deal with this. It's not a huge deal but keep in mind you want to provide your plants with the most optimum nutrient solution possible which means you don't want to see any locking out whatsoever.