White Rhino Yellowing leaf Edges Help

OK This is my first grow indoors and i have 4 White rhinos and 4 haxe 19x skunks all growing under a 400w hps placed about 18 inches above them all plants are growing in same sized containers and are in soil miracle grow plant feeder soil package says will feed up tp 3 months all plants are about 2 1/2 weeks old and have 3 sets of limbs i water every 3 days but now the white rhinos are starting to yellow around the edges of 2 of the plants but not the other 2 and the haze 19x's are fine too this is my first grow indoors and first time growing strains like this please help

the MG is probably burning them, it's very hot stuff for little plants..
pics would help us allot..

mick.

Some strains are more affected by MG then others, probably the WR is not liking all the NPK so early in life, remember it"a a Weed..."-)

Miracle-Gro Ingredients ( I believe they use this in there extended release soils )

The All-Purpose Plant Food has a 15-30-15 ratio, meaning that there is 15% Nitrogen, 30% Phosphate, and 15% Potash.

The primary ingredients in the Miracle-Gro powder are as follows:

â?¢ 5.8% Ammoniacal Nitrogen
â?¢ 9.2% Urea Nitrogen
â?¢ 30% Available Phosphate
â?¢ 15% Soluble Potash
â?¢ 0.02% Boron
â?¢ 0.07% Copper
â?¢ 0.15% Iron
â?¢ 0.05% Manganese
â?¢ 0.005% Molybdenum
â?¢ 0.06% Zinc

Compared to Botanicare Pro Grow 3-2-4 & Pro Bloom 2-3-5 that MG in one hot number, not to mention out of wack for the stages of MJ growth...

i have transplanted out of the mg soil and into regular soil plants seem to be doing well now they are now 14 inches and looking great i will post some pics later today