This is extremely common when using myriad dry amendments in Coco, lots of Mr. Canuck victims come to this site every day. What I would recommend, you probably will not like. I would buy some Maxibloom, and start feeding it like coco should be fed-frequently and with tons of runoff. I wouldn't flush those pots with plain water, it will just make matters worse. I would flush WHILE feeding them, though I'd start at the low end, say 400 ppms the first feed, and go for 30-50% runoff. Do that for a few days, then your media will be mostly flushed out, although those amendments will keep breaking down, you'll continue to flush them out while feeding-go up to 600 ppm per feed, 5.8 PH with 20% runoff. How often is up to you, some people feed coco twice per day by hand (like me), some people feed 5 times per day with drippers, and some treat coco exactly like soil, though I wouldn't recommend that in your situation. Doing this will snap your plants out of lockout, re-adjust their PH (through frequent feeds), and kickstart their growth. I recommend Maxibloom for this, because it's an easy to use, reliable, 1 part formula that is complete, but you could do the same thing with Jack's A&B if you want.