This is my first grow I got a 3ftx2ft cupboard split into two 4ft levels. Both have a 250watt hps lamp. The seedlings are 8 days old and seem to be stretching quite a bit. A couple have fallen over! I started germinating with an ordinary 60watt bulb on each level. Today I swithed for the hps's how far should I put them from seedlings to try to rectify the problem. Any help greatfull, cheers guys