Newb grower couple questions

hey guys i just started my grow room 24 plants got a few issues ill give some background info first so anyone reading can try to assess my issues.

Light: 430watt HPS sodium, using a rockwool medium with hydroponic drip light is on 24 hours a day during vegitative state at the moment also have some flouresents in there as well we have been watering twice a day for 15 minutes with a 1/2 gallen drip but just brought it down to one 20 min watering session a day due to a white and green mold forming on the rockwool cubes ontop of the rockwool slabs. is this an issue? if so how do we erradticate the mold from the rockwool. it didnt really show up till we started adding nutriants about 4 days ago this is about the 20th day of growing also we have a high ph that we have not been able to get down its about 7-8 and i know that rockwool needs to be about 5.7 so i dunno if this caused our mold problem or not but any help would be, well, helpfull thanks.

ps i can probably add some pictures if need be

mod is truly an issue in a grow! you must be doing something wrong there really!!

also, normal HPS are no good to veg with, for that rather use MH bulbs or several CFLs with 6500K/cool white spec, that is way better then HPS for veg. i would also cut back the light to 18/6 safes power and plants have time to rest and grow

this is my set up the mold issue and a couple of the plants sorry for the darkness to bright with the HID on to take a picture maybe better pictures later