Hey i was just wondering if i could just switch from 18/6 to 12/12, or would that shock the plants? should i slowly decrease the amount of light time? and right now im vegging with one 400w mh and i have 5 plants. would 400W be good to flower? if not i have another 400w mh, should i use both?
18/6 to 12/12
- Thread starter luca420
- Start date
bongrippinbob
Well-Known Member
400 watts is plenty depending on your space. I would go no bigger than 3'x3' with a 400watt light, and 2'x2' or 2'x3' is better.
When I go from 18/6 to 12/12, I like to give them 24hrs of darkness just so they can build up the chemicals that trigger flower. You can go straight to 12/12 from 18/6 without any problems. But giving them 24hrs of darkness will get them to start flowering a couple of days faster.
When I go from 18/6 to 12/12, I like to give them 24hrs of darkness just so they can build up the chemicals that trigger flower. You can go straight to 12/12 from 18/6 without any problems. But giving them 24hrs of darkness will get them to start flowering a couple of days faster.
mane2008
Well-Known Member
Naw you dont want to slowly decrease bra. if you gon do 18/6 like homeboy said do 24 hr of darkness this will help show sex faster and trigger flowering.
meathook666
Well-Known Member
my plants went thru 36hrs of darkness. it worked out very well..
NewGrowth
Well-Known Member
Just switch it from 18 to 12 you will not have any problems. You should use both lights if you can control the heat you will get a better yield.
bongrippinbob
Well-Known Member
If you are growing in a 2'x2' area and keep the temps down with 800watts, the plants can't use all that light without CO2 enrichment. So you are wasting 400watts of electricity every hour. If you are up over 75watts per sq ft you should be using CO2 to get the most out of your grow. If you are under that 75watts per sq ft, you don't need the CO2 and just need to keep the temps under control.
Cr8z13
Well-Known Member
I'm a few days from switching to 12/12 and all of my plants are already showing sex(female). Is 24+ hours of darkness really necessary, or should I do it anyway? Sorry for the threadjack.
bongrippinbob
Well-Known Member
The easiest way to get CO2 to the plants is to get a co2 setup. You can get them on ebay for like $140. Make sure you get one with a flow meter, solenoid, and regulator, not just one part of it or one with a bubble counter. They are for fish tanks, not plants. THen you need to either rent or buy a co2 tank from a welding supply store. You will need some timers to run the CO2 solenoid and your fans, a digital one to run the CO2 part, and use a CO2 calculator online to figure out how long to have it on.
ANd to Cra8z, the 24hrs is not needed so to speak, but it does help to speed up flowering. When you throw them under 12/12, they will take about a week or so to start to bud. With 24hrs of darkness they will start to bud a little quicker. After the plants have gotten 12hrs of dark, they begin to produce the chemical that makes them flower. Having the lights off for 24hrs will allow them to build up an abundance of this chemical and thus speed up the start of flower.
And for
ANd to Cra8z, the 24hrs is not needed so to speak, but it does help to speed up flowering. When you throw them under 12/12, they will take about a week or so to start to bud. With 24hrs of darkness they will start to bud a little quicker. After the plants have gotten 12hrs of dark, they begin to produce the chemical that makes them flower. Having the lights off for 24hrs will allow them to build up an abundance of this chemical and thus speed up the start of flower.
And for