I'm using the GH trio as well and I have some plants that need full strength and some that take a quarter strength dose. I use them in soil but if you don't drain to waist like 20 to 30 percent of the water I find that it builds up in my soil and burns the plants. They're ment to be used together all through the grow, not grow in veg and bloom in flower. All 3 throughout. I made that mistake when I first used the trio. With the powerful lights plants tent to need more nutrients to support the accelerated growth that comes with it I have 5 plants that take full strength and 2 that take half, and the ones taking full strength could use a touch more. It depends on each individual plant. It's better to make individual batches for the plants compared to one big batch for all. But like you say if it's at the tips they could be getting too much or getting buildup at the roots which could be fixed with a few plain pHed calmaged waterings or a flush of give or take 3 gallons water for every gallon soil. Do you measure ph in and out or EC in and out. Would give you a better idea of what's happening in the root zone. Hope this helps.
