You do not change your soil for the diff stages of growth. Check out the web on How to care for your soil. Then recycle it when your done with it.
are you retarded to ask me something like that. you mos fucking stalk me and look at all my post what cop grows you smart fuck?
Are you a cop? You're posts are retarded.
Well with 800w you can cover around 2msquared of space, which will leave you some room to work around the plants. I would say then you could get around 18 good sized plants, or go for double that on a SOG (i.e basically turning the plants straight into 12/12) With big yielders you can get around a kilo per grow if you play your card right. Perhaps add to cfl's in their for extra cheap and easy to get lighting.
Ok man look at my album on my profile I put the plans I drew up on my albums and it is labled bong hoger grow op.
I think a 250 CFM air booster for like 45 dollars would be enough to exaust the hot stale air out. If you hold on like later this afternoon I will draw up some plans for the room you described with the same measurements and a 400w Hps.
Yes definatley will need ventilation. I have a 4x4x4 veg box with two intake and exhaust. I tried to run a 400 mh and it got way to hot, so I went with two 4 tube T-5's and it works great for veg. If I were you and needed to keep it sealed, I would put some plexiglass under the light and above the plants. You would need to have it adjustable so you can move it when you move the light. Then you can exhaust the top half of your box. Either way man, you are going to have to cool that box and it will get very very hot with the hid. Maybe try some T-5's instead of the HID if you can't get some major airflow through there.
You will def initely need ventilation coming into that box. I would suggest an in/out ventialtion of some kind. It will get hot in that box sealed up. Very hot
Hey man, sorry for the delay in getting back to you. As for your heat question, in a room tht big with 2 400s you should be fine witht he heat until summer comes. This is assuming you have air-cooled hoods. If not, I would make sure you have a good exhaust fan and keep them atleast a two feet away from the canopy. You will be able to tell if they are getting to hot. The leafs will start to bleach out and curl up like canoes. If this happens just raise it some more. You can get away with temps in the high 80's in the room. Put some oscilating fans in there too, they are cheap and they help alot. I tend to agree with ST that you may get away with only one light. I hope this helps.
I don't think you would need as many lights then unless you are growing a shit load of tomatoes, and I don't think that is economical to do unless you are doing it commercially. So for 3 auto I would go for 1 400 if you want to grow inside, that will give you excellent lightl penetration over a metre square.
If you do want to go to the expense I am sure there will be online shops that ship. Not sure about hydrow or grow shops in SA.
to name a few online.
PM me if you need any help bru.