you definitely should add the 2*600 hps along with the 1000 halide for ur flowering room, i previously had 2*1000 hps and the monthly bill was runnin bout 50-60 dollars US, but i also had hundreds of plants. If you have the funds to keep up with the elec bill, you should combine, it will increase the amount of trichomes because of combining the two spectrums and it will help bring out the alternate colors of the bud! Ive heard that the combination ballast of the hps and mh was more likely to short out on you because of the distribution of the power. just get two seperate ballasts, to be safe! GOod luck man!