Hello I am a new grower and i have a 10 inch plant that is 1 and 1/2 months old. i have it on a 23 hours of light cycle right now. It is in a 2 gallon plant pot soil is miracle grow. I water when i feel is right which is about once a week i stick my finger all the way down in the soil and feel for moisture if i dont feel any then i water. 1 foot away from a 150 watt light bulb used for lizards. for the last 2 weeks the the plants leaves have started turning yellow slowely in a weird way and i am puzzled. it is worste at the bottom the plants leaves start to turn yellow starting at the tips and works its way thru the leaf. the newer leaves are starting to get it and 6 of the 10 branches there are so far have yellow tips. the 2 lowest ones have completely died and i want to save the rest before its too late!! please help!!