My veg room currently has 3 trays of plants in hydro. 2 of the 3 lights are MH and one is HPS, all 1000 watt. I move clones in under a MH and then as they grow they get separated out under either a MH or HPS bulb. The plants under the HPS lights look terrible. Plants that were once flourishing under the MH, vigorous new growth, no brown leaves, begin to deteriorate under the HPS. They don't die but all the leaves begin turning brown, the growth becomes very very slow (but doesn't stop, they do still grow a little), and the new growth is lighter green than others. Once I move the plants to bloom under 1000 watt HPS they really pick up the pace, growing as they should, no more brown leaves (except the normal amount, of course), and form buds just like all the plants. I really have no idea what's going on. I don't know if the placement of my AC could be a cause; this tray is closest to the air output so maybe too much cold breeze? I also have an oscillating fan, which this tray is farthest from, so maybe there's not enough breeze?? I am not sure. If it is the HPS light, would a conversion bulb remedy the problem?