Tips of leaf have turned yellow

Am new to growing and luckily my first plant (donated) turned out to be a female, I have a couple of questions which I cant find the answer to in the FAQ section so I was wondering if there are any experienced growers out there who could help me?

The plant is about 2.5' and has been flowering for about 2 weeks.
Since flowering started the very tips of the leaves have turned yellow, it doesnt seem to be spreading into the leaf and the plant looks very healthy otherwise.

Also some of the pistils lower down on the main stem have turned amber already, why is that as the flowers are nowhere near done.

I would appreciate any help in this matter.....Thankyou.:)

yellow or brown tips usually means you are having a fertilizer burn..

can you post a picture

Thanks for answering Garden Knowm your opinion seems to hold a lot of weight around here.
Last time i fertilized was seven days ago and I used Miracle Grow 15-30-15.
I know this gets a lot of stick but like I said I am just starting out, will try to get a picture up today, just need to get some batteries for the camera.

Here are some pictures of the plant and growroom, sorry about the quality but it is the best I can do at the moment.
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My specs are as follows:
Growroom = 5'x4'x8' high
Light = 600 watt HID lamp with dual spectrum bulb
10 litre pot with 80% 20% composted bark/perlite mix
Watering about every 3-4 days
Nutrients are Miracle Grow 15-30-15
Temp ranges from 25-29 degrees celsius
Humidity ranges from 40% - 60%
Intake and outake fan and ocillating fan inside growroom.

Thanks for any advice.:)

Nute burn is a definite possibility, as Knowm mentioned.

Also, browning, crispy tips can be the onset of potassium deficiency. This is not to say that the ferts do not contain enough potassium. One thing to watch out for sometimes is to provide equal amounts of Phosphorous (P) and Potassium (K). Excess P can lock out access to K. Sometimes switching to nutrients with equal portions of P and K can balance things out (your MG ferts had twice the amount of P for K)

No worries about the amber hairs at the bottom. they're just the older flowers, I imagine.

good luck!:thumbsup:

Thanks SmokeyD.Bear its nice to know that their is so much help out there.
What nutrients do you suggest instead of miracle gro? I have the cash just not the knowledge....

I don't know if any one brand is better than another (it's all up to your preference and what's available around you) When correcting deficiencies with macro-nutrients (N-P-K) you just need to treat with a balanced fertilizer...all the numbers the same. Schultz sells liquid plant food real cheap, that is 10-10-10. For MJ you might want to dilute a bit (this will also help defend against nutrient burn), preferably to a 5-5-5 concentration ..just use half as much recommended fertilizer to water...

For other nutrient deficiencies it will all depend, I suppose. I'd just ask around if and when that happens.

Thanks for the help mate will take it into account, loving growing as it is one long learnin process and gaining knowledge is my favourite pastime, thanks again:) :)