3weeks?? What are you using for lights?? A few flash lights?? 3 weeks they should be atleast a foot and bushy... I would say put em under 400 mh for 24 hours no dark and lay low on nutes for another week or so until they grow some!! Are you over watering them?? Wait till the leaves start to drop...
Flush now don't wait till it dries up it will just suck up more nutes and prolly kill them... Flush at least 2-1 with tap water then 1-1 with ph'd water... As for feeding nutes at 4 weeks I use full strength every other watering.. I use DNF so for me it's 5ml of a&b per liter... And mine love...
Oh and pumps use any where from 25 watts all the way to 500 watts (big ones) fans 8 inch inline is about 300watts house hold osculating fans are I think 125 and then you have extra hydro lost in wires maybe cost???? Idk timers use very little guess that's about it for a small grow hope it helps...
In ontario on peak rate is .09 cents so if you calculate it at that it's 1000 times 12 hours = 12000 which is 12 kilowatts so 12 times .09 = 1.08 so it costs $1.08 a day to run a 1000 watt light for 12 hours.. Let say wit your 1000 mh and 400 hps and fans pumps and other times in the room you...
Well I have never gone with anything buy 1000's so flo's is really nothing in comparison if I was you I'd get those big cfl's and hang them around the plants I think you would be happier with the results with those
Yup water when it's about 20% dry I never let them dry right out soil will get air pockets sometimes and no water reaches it killing roots after time ... I water about every 4 days
Can u see the roots at the bottom of the pots? If so move them ... My tap water comes out at 7.9-8.2 ph 5 gal water pale I put roughly 15-20 drops of ph down and that get it to where I want it ... Just spend the 120 on a ph pen well worth the money!!!
What size pales are you going to put them in??
I would say u might end up with 70-140 grams ..... Being your first grow take your time and get them to flower and finish before worrying about what your going to get ... as u get a few grows under your belt you will get better and more yields at best you might be able to get close to a pound...