First grow plants having problems!!!!! help

Hey guys i need your help
My ladies are in the 3rd week of flowering and they are giving me probs so i thought id post on here and see what u guys think

They are yellowing on the bottom fan leaves and tips are turning down on the entire plants. The plant i didnt top tips are really turning down. I water them every 3 days or so with fox farm big bloom and tiger bloom every other watering. they are under 4 flour tubes. one 400hps and a ufo led. I ph my water that i use(rain) everytime the best i can(the ph tester i have is for fish tanks need to get a digy one) the temp is about 65 70 at dark and 78-82 during lights on. PLEASE HELP i need to resolve this before i order some seeds these are just bagseeds i thought i would give it a shot so i could work out what i dont know before i get the good shit

well not for sure but it could be a N def.
the nutes you are using have very little nitrogen in them

do you have any FF grow big?

hey dont worry thats normal simple fact is that the flowering nutes have less nitrogen n more phos aslong is the lower leaves and not all over the plant now what u can do is add a lil bit of veg nutes to your watering it helps them stay nice and green a couple of buddies experimented n some r experimenting using veg nutes n is going great for them im to far in my grow to try it but i will in my next oh bs becareful w/ fox farm is easy to nute burn good luck

I have ff grow big. How much should i use. And how much of tiger and bb should i be using i mix all my nutes up in gal jugs. Can i also spray feed the grow big? and do they look stunted for 3 to 4 weeks of flowering the buds really havent developed yet thanks allot for the advice

well my schedule says for the 3rd week give 2 tsp per gallon of grow big, 2 tsp per g. of tiger bloom, and 1 Tbl per g. of big bloom.

i don't know about the spray feeding thou
they don't look to bad as far as height, just need some N. nutes

try that and see if it helps out at all, might that a few days to see a change.

Alright ill do that and keep u posted im gonna need advice on harvesting too i screwed around before with a plant outside turned out to be female it was pretty dank but no much bud. Some stuff i had the hay smell to some i didnt i dont know if my room wasnt cold enough or if i dried it to fast cuz the humidity was 35 to 40% i a noob trying to grow some good personal thanks guys burner