could use help...

im trying to save this little sprout my friend gave me but im not doing too well.
its only 1.5" and just getting its second set of leaves.
ive got it under a fluro 16\4 (just till its a little stronger)
but now the tips of the first leaves are going brown.
its not ferts cause im not using any, but i suspect that my light may have done it... any opinions as to how i can save this ones life would be great.
peace... and a stick of green. :o

Its hard to say because you didnt mention what kind of flouros your using.Do your flouros get hot?If so thats probably your problem.Move your lights a little farther away till you can get a better light.A 250 HPS would be ideal for your situation.Are you sure you havent used any fert?Sound kind of like nitro burn to me.If thats the case ,just flush with clean water.