I never expirience this problem growing for years with great success but know something is wrong i belive the heat is the problem 26 to over 30 the last 2 week's my plants looking most good but i see another plant the first leafs are dying also so I fearing that my plants dying off... I add 3ml H2O2 to the water for more oxygen hope that's helping fan blowing 24h lights are only 55 watt cob for the first weeks so what's the problem here? Maybe adding more H2O2 and give them a oxygen boost but how much? I never over watering growing coco for year's..