my plants died overnight

when they were doing good i used to give them little bursts of co2 every now and then with the vinegar and baking soda thing; not knowing if that was actually doing anything or not. but what would that do if i did that while i'm doing my flushing ang reviving. Or should i just clean flush it every few days and just let it be? will the fan hurt/help it while its trying to come back? And is 2 and a half feet too far/close for that 1000 watt while they are struggling?

im a noob cant answer most ur questionsdont know about the co2 thingy but i think ur light is ok at 2 1/2 feet away. i use a 400 watter i keep mines 10-20in away

i think u plants have a chance to come back flush them once and then only water when soil is dry or like i do i wait till the pot is lite in weight which is 2-3 days u should feed with nutes every 2-3 watering= water/water/nutes/water
i think ur problem now is over watering and over feeding