plz help!!! got pics- 1 week into flowering

hi i would be grate full if any1 can help (i am first time grower)

plants are on 12/12 cycle- ph level 5.8- temp average 80 -600 watt light- fed 3 times a day consitantly- grown in rockwall cubes

the leafs are drooping limping dying at the bottom, the leafs at top r fine. what is happening? plz seee pics

is this problem gonna spread up the plant

phosphorus deficentcy add some ,or you might need more ferts ?,

pull off the worst leaves and make shure youor not suffocating the plant how much are you feeding them when you water

im u ssing wilma drip system which goes on 3 times a day for 15 minutes