Bottom yellow leaves

This is my 5th or 6th grow and my plants are about 5 inches tall and 2 of my plants the very bottom leaves are turning yellow and when they fall off the next bottom ones turn yellow any help please

they're hungry.... they are taking nitrogen from the bottom leaves to use in the rest of the plant.... need to start feeding with something high in nitrogen

thank you I will do that right now

dont go crazy with it though.... just follow the directions on the label... what kind of nutrients do you have to use??

I use foxfarm and never had a prob thats why I dont know why they are doing this I have all the testers and all the extras like superthrive and hygrozyme

Ill take a pic right now

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