Wanna nip this in the Bud ( No pun intended)

Hey guys and gals,
Generally new grower here, although I have tried in the past, all attempts have failed, so i decided to do it right this time ( Lights, box, vents, fans etc the whole shabang) I will be thoroughly disappointed if I fail again. I have a couple Dutch Treat autos on the go, and noticed a bit a yellowing on the tips of the bottom leaves. I dont want this to get any worse, and would like to know whats going on. If someone could point me in the right direction. Ive used veg nutes once, and at about 1/2 strength. about a week and a half ago. Other than that its been water only.

if the leaves continue to get yellow and you haven't given any more fert, then it might be a good idea to give a little more fert. but don't do anything unless the yellowing gets bad. what soil are you using? what ferts are in the soil?

Come on, tell the truth. You fully intended that pun!

I completely forgot what soul I used. Just an organic mix with perlite, 10/15/10 fert.