Very generally speaking ----- this is just my opinion ----- bottled nutrients are best in soilless mediums. Actual soil does best with organic/dry amendments. Again this is not a given, just based on the grows I've seen and walls people sometimes hit, like yourself here. Also make sure you're not feeeding your soil with every single watering. Soil, a lot like people oddly enough, does best with clean drinks of water between "meals".