First Grown need help

I know if I searched long enough I would prolly find the answer to this so I apologize ahead of time, its just that Im 40 odd days into flower, all tips are turning brown even in along the bud site the sugar leaves are and Im not sure what it is. Also of course plant growth and weight are also slowed right now. Any and all help is appreciated and rep+ for quickest legit answer.

SO helpful info is: running in an aerogarden 6 saver res, using GH 3 part series, local water from a bubbling spring, 12/12 since june 28, nirvana blackjack, 2 150W CFL's and 2 26W aero lights in the hood above, oh and the other plant which has been stunted for a little just starting getting hairs about a week ago and now some of them are turning armber and dieing off before even really developing much? also waiting on ph meter in mail, been using the liquid that is retarded to try to get accurate reading from. thanks guys

Ive never gown in aero but it could possibly be that the buds are pulling most of the nutes and therefore the leaves are slowly kinda dying from it. Maybe the plant is asking for a bit more nutrients. The plant seems to be doing ok though.

yeah I mean they are big bushy plants, buds are staying on the smaller side, so maybe it is not enough nutes, I just dont want to overdo it, and dont have a ppm meter to test

well, way I see it, straight water never hurt anything so I freaked out, and flushed my res and got all the built up salts at the bottom off and just put in ph balanced water. Till I hear from forum fathers and one of them says exactly what it was I will treat it as over nutes. Roots were rediculous in that little res and hopefully in all the commotion I didnt hurt anything too bad, of course it was right as lights off so they went off half way through the emergency flush. Any ideas from you long time posters?

Would appreciate thoughts instead of just views guys... Did the flush and this morning most leaves are looking a bit brittle (maybe leathery is a better fit) looking and they seem to have a slight rolling under happening at the sides of the leaves. Anyone?