Leaves yellowing and burnt on tips

my apologise for no pics I took a lot but I cannot find the damn cord to hook to comp. I have searched forums and read advice and I think I am on the right track but if someone could help would be well appreciated.

I have 2 plants that are 17 days old in miracle grow soil, ph 6.2 with plenty of NPK or so my soil testers say. 7 days ago I started to notice yellow creeping from the tips somewhat down the leaves but only between the veins, also a couple of the old leaves twisted and curled a bit. So I added a 2 8 4 mixture with Iron Zinc and Maganese(yesterday). The day before I added the nitreints I put on the 400 metal halide conversion light hps ballast. Temps ranging from 75 -86 at 18 and a drop of about 10 during the 6. Humidity between 30 and 50, its hard to keep it up, I am using an evaporator and it sprinkles a very light ammount of water on the leaves while it is on half the 18. off on sorta thing, whenever i refill water... One of my plants became droopy in the stem so I added water and it seemed to help(11 days into growth.) The same day I added nutes I noticed that the tips of a couple top leaves look slightly burnt and curled upward so I moved light from 1 foot to 2 feet away. and bought 2 more fans now i have 3. (this is in a closet with door slightly open. Also that same day I noticed little light collored bugs crawling around the soil. Now today the burning looks slightly worse and I havent moved the light but I moved the ballast out and I think its dropped about 5 degrees since.

SUMMARY OF SYMPTOMS
every leaf exept the bottom 2 have that yellowish look to it, the middle leaves are coloured yellow along the tips on the outside of the leaves and the yellow sortof fades in to the centre of the leafs but no yellow on veins. The knew leaves are lime green.( I thought iron zinc and maganese but its been a day and they havent really changed any.)

top couple of leaves (I noticed about 6 leaves that have that crisp look right at the very tip. One tip is even curling straight verticly up at the very tip, like 5mm.)at the very tips have a burnt look that can crack easily and is really dry. also the top leaves are convex toward the light. I assume heat stress, or do you think my LIGHT is STILL TO CLOSE?????

One of my plants is still droopy so I put somethin in to hold it more verticle. I think it has grown on an angle for to long and doesnt want to change it.

The bugs what can I do about the bugs, cigarette but water poored into soil??

Now a couple more leaves on one plant look burnt and are sagging downward.

heres a crappy pic, you can kind of see the yellow brown crisp edge on the leaf closest to us, there is a couple more like that, this is roommates camera other camera take way better pic but no cord damn hey,.

sry second from the left is brown crisp at the very tip and the one next to it has scorch alont the side closer to us, also the bottom leaf on the opposite side is scorched a bit to, could it be humidity to low to hot of room, nute burn, i kinda doubt it but it could be.

Sure looks like nute burn to me.

Sounds like you have WAAAAAY too many ferts in there for your plants. Your testers says you have "plenty" Exactly how much is "plenty?" Maybe your idea of plenty and your plant's idea .......you see where I'm going with this?

You need to flush with ph correct water (6.2-6.8) usually 3-5 x size of pot (1 gallon pot....flush with 3-5 gallons of water.) Then make sure the soil runoff water coming out the bottom is the correct ph and give a final ph correct flush with 1/4 strength nutes..

thanks, shitty, personaly I don't think it is but if it gets worse I will know it is. Also some of the leaves right where the stem part attaches and a quarter way across them is all wrinkly, really fine wrinkles.

because it only happens on the very edges and tips that are curled a tiny bit

the crispiness and yellowish brown I mean, sry

yes i know what you mean.....here's the progression....you are on about step two.
1. Edges and tips will wilt and curl.
2. Edges and tips start to burn....rest of leaf begins to look damaged
3. burning continues until the entire leaf turns crispy and dry
4. Leaf burns off.


good luck.

PS...get yourself some good organic bug spray for the bugs....follow directions CAREFULLY. I like Fox Farms Don't Bug Me.