yo im runnin 2 1000w lights right now (1000w mh & 1000w hps) and im about 2 get 4 more 1000w hps ballasts, lights and hoods and im gunna split each 1000w in2 2 600w light...(the guy at my hydropontics store said the 1000w ballasts could run 2 600's) and im gunna have a 15x15 (aprox) space...