PH too high... Are my babies going to die? HELP?! (Pic included)

Hello, my plants were looking really good, strong and growing fast. Than I changed the nutrient solution and noticed the PH was too low (in the 4.0 to 4.5 area) I added some PH up and the next morning the plants were all wilted and some leaning so far over I thought they were dead. Some of the leaves were curling at the tips. The PH skyrocketed to over 8.0 (the PH sticks were dark blue) I tried to lower the PH and it wasn't successful so I dumped out the solution and added 6 new gallons of distilled water and nutirent solution.

My question is.... Are my plants in shock, are they dying or are they just plain ol dead?
Please see pictures attached. Any advice would be good. PS the current PH is around 6.2 to 6.5 in a bubbleponics hydro kit.

Just in shock mate... Anything that is barely alive or limp, has a will to keep doing so.... Give them a few days to recover... I see you are growing in hydroton, so just keep to your regular watering schedule, which should be about 15 mins every hour... I grow in Hydroton too....