First Grow Outdoor / Indoor Purple Punch Autoflower

Moved into die 2x2 tent by AC Infinity. It's now an indoor grow. I am using predatory mites because of a very small thrips infection. That's what you can see on the leafs and the soil. I scattered them with bran as carrier material. If anyone has any ideas how I can get the leaf rot of older leafs under control, please write me. Probably always fed too little amounts of water too often. Which means that I literally sunk the pot inside a tub with water to completely hydrate the soil. Hopefully the Leafs are stopping to get brown now.