Root rot even using a little water. Can't help It!

Hey there one thing I like todo is set my exaust fan to not run for like 45 min then set to run for 15min this helps the air in the tent heat up and evaporate air from the soil then everyn45 min the exhaust fan will clear the tent letting it start over. Also next time if you use promix HP it is high prosperity witch means it I'd airy and dries out quickly also if you mix extra perlite into it this will help even more also if you put about 1inch of perlite in the bottom of your grow pots this will help a ton with drainage. The key to good roots is having a good start as a seedling. When the plant is still small make sure to only give the seedling like 45 sprays from water bottle then1dt few times you water untill roots hit bottom the container then when you transfer the plant to large pot makensure you are only watering on the egmdge of the pot making roots reach outwards. After plant hadnrooted the pot well then only water when soil is completely dry canntake 1o day or so sometimes durring early veg. Plants will start to look nice for a period then when soil gets really dry plants will start to sag a little this is when you want to water When plants go into flower I like to let them go as long as possible till they look stressed from not enough water then I subtract 1 day from that and then that's my water schedule for flower for the plant. One very important thing is to eater plants individually just because one plant is ready to be watered don't be lazy and water all the plants at the same time. They will all drink up water at diff paces