I will start a new grow with new seeds. I will use Advanced Nutrients fertilizer. I will use this fertilizer for the first time.

depends on size of seedling container and the substrate you use. never superficially irrigate. that promotes all sorts of problems. always water entire pot. if you don't want to water a seedling, use a humidity dome until it sprouts. this will maintain moisture level in the substrate by limiting evaporation. Remove it immediately when the plant sprouts. You should have several days before you need to irrigate again and the seedling will have enough taproot that it won't be a concern to do it properly. always water entirety of a pot. never try to choose how much water it takes. it takes what is required. with soil grows, you can irrigate until a minimal amount of runoff occurs. in soilless you want 10% excess runoff, religously. Wait for top layer to dry and repeat. you learn the volume required in hindsight. it is not a volume of water you choose.