Newbie question

I have 4 ladies going never done anything like this before, they are now 7 weeks and in bloom, They am in 12" pots soil is tomato grow soil. Had the girls given me and the 400 watt lamp. I have lamp on 12 hours on and 12 hours off, I feed every night with a mix of 10mil pro XL too 2 litre water. that is half a litre to each lady, Every night for the past 5 weeks. Question is am I doing ok is it the right thing to do? I made a post about brown tip on some leafs not all, "WAs told over feeding" and need a flush! here is a image of my girls, each time I feed I am always touching soil and find it always dry hence why i feed as I do. am I doing right or am I doing wrong is my question. Also how long do i leave them to grow for? I was told 10 weeks is that right?
Any input will be very greatful thanks a bunch guys...
picture was taken today do they look healthy to you?

thanks

They look like a relativley happy bunch of sativa. The do not look burnt in anyway~ yet. If you continue to feed and water everyday, they will overdose. let it go a week before resuming YOU probably will have about 12 weeks as it is a sativa. They gen take a little longer. Dont feed next week only water, wait till they are compleatly dry before watering again. The little bit of yellowing then browning on the tips is from a little over water not from nute burn, the two look totally diffrent, so good job they look great so far and don't listen to a bunch of bullshit about flushes that is when your plant has pretty much had it. And as a last resort, And NEVER 3/4 through a bloom. What an Idiot that guy must be. You will start your finall flush out in a couple weeks to rid soil of unwanted chems, anyway! so why stunt your girls now?

If your getting brown tips, it's most likely from overfeeding. You don't need to flush, just back off on the nutes. Try feeding one day and plain water the next. In derterming when to water, you want to check about 2-3" deep into the soil, not just the surface. If it feels dry 2" down then water, if it feels moist, it's fine. A moisture meter is a good idea if your unsure. This is the one I use. Stick it 2-3" in the soil, if it reads under 4, water, over 4, it's good.http://www.ebay.com/itm/Lusterleaf-Digital-Instant-Moisture-Meter-/181072871411?pt=LH_DefaultDomain_0&hash=item2a28c8bff3
Harvest time varies. The best way to tell is by looking at the trichomes under a microscope like this http://www.radioshack.com/product/index.jsp?productId=2179604
They start out clear, then begin to turn milky white and then amber. If you know your strain, you can look up when the best time to harvest is as some strains benifit from allowing the trichomes to go amber. In general though, you'll want to harvest when most of the trichomes have turned milky white as the amber color is usually means that thc has peaked and is now begining to break down.
Happy Growing.

what are the numbers on the pro XL ?

they look pretty healthy, but also dark green, might turn down on the nuts or even better get one with a high ratio of P and K and little N (Nitrogen = fist number on the bottle)
look like they are ready for a bloom fertilizer instead of one for the vegetive stages (if that is the case ? do some research)


and about watering, its nice to see a little run of from the drain holes and then let it dry out a bit, not flush (I rarely do but Im also in a organic soil mix of me own) but so your sure all the medium/soil is wet

Thanks for your replys Last night the soil was dry, so not added any feed only half litre of water . Tonight just put lamp on and soil was again dry so again put in water no feed. will it harm them not adding feed for a few days and just water instead! never put plain water before till last night and tonight. will do same tomorrow night then carry on with feed after that. if that's ok!! As i have stated my soil is always dry every time i check at 9pm lamp on.. and is when i always feed 9pm. never look at them till following night so 24 hours is when i look and feed.. so I feed every 24 hours not any other time..

Instead of feeling the top of the dirt, which tells you nothing about moisture level at root depth. Next water, water til you get run off that way you know soil is completely wet. Fill empty pot with dry soil, check the weight.. When your potted plants feel close to the same weight then you know its time to water... By not watering completely everytime you will get more salt buildup in soil.

Thanks mate, you know i am growing these and i don't smoke lol . just a little hobby see if i can grow them i prob will give them away when they am ready, i think i will get 4 ounce out them, someone said 4 plants a ounce per plant if i am lucky as im not growing in proper conditions oh well its been fun so far.