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seedlings 4-18 days. how far from 400mh?

budman678

I come from the land where the oceans freeze
Veteran
Hi guys. I have 3 girls that have outgrown their beer cups. i put them in 2gal pots before final 5gal transplant. i also switched out lights to the 400mh. how high should i have the light from the tops? i also have 2 deez x Sour Diesel Kushes still in beer cups. They are 4 days above soil and have thier first 2 true sets of leaves.

sooo, how far should i keep them from the big 400metal halide. temps are in the mid 70s so heat is not and issue. also have a small floor oscillating fan on low.
 

budman678

I come from the land where the oceans freeze
Veteran
i am running a 250watt cfl but literally JUST place them under the 400mh. i am thinking they are about 3ft or so above the tops as they sit right now.

is this too much, should i drop it close?
 

Mt Toaker

Member
Depends on how hot the light gets. . . Generally 12-18" depending on your air circulation. . . You can have a home made cool tube easy, buy a Bake-A-Round and you can have it as close as you want. . .
 

FreezerBoy

Was blind but now IC Puckbunny in Training
Veteran
Seedlings expect the full power of the sun in all it's blazing glory. They laugh at your puny 400, kick sand in it's face and walk off with it's girl.

However, you lied to them. You said the sun was a 250. They believed you and built themselves accordingly. To simply chuck them under a 400 now is the equivalent of the sun going nova. They require acclimation. Start with lamp extra high, place seedlings under the 400 at "noon" (so only half the day is under the 400 followed by a good night's sleep) Lower the lamp a few inches a day until it's at the desired height.
 

budman678

I come from the land where the oceans freeze
Veteran
i have great temps in there and some air movement. i have the hood around 3ft above the canopy. i will slowlyy lower over the next week. this seems acceptable. i will also reconvene after the first couple days under the new light. change height accordingly
 

420shooter

Member
Seedlings expect the full power of the sun in all it's blazing glory. They laugh at your puny 400, kick sand in it's face and walk off with it's girl.

However, you lied to them. You said the sun was a 250. They believed you and built themselves accordingly. To simply chuck them under a 400 now is the equivalent of the sun going nova. They require acclimation. Start with lamp extra high, place seedlings under the 400 at "noon" (so only half the day is under the 400 followed by a good night's sleep) Lower the lamp a few inches a day until it's at the desired height.
Thats what I do. 3ft then decrease by about a foot every day. I just stick my hand at the top of the plants and feel the temp. When it starts to feel warm after a minute I raise it a few inches until the next day. Your room temps can be very different than the temps under the light.
 
G

grassott

do the hand test. place the back of your hand under the bulb. if your hand feels too hot then so will the tops of your plants. i'm guessing you got the fan pointing towards the bulb, which will still give your plants slight movement?
and why change from 250 - 400w? you're only giving yourself a bigger electric bill. if the plants are still vegging and they was growing fine (must have been fine in order for you to need to transplant) then the 250 coulda still be used for a few weeks more IME. i grow plants 4 ft tall with 250w of cfl lighting, aided with a 70w mh.

oh, and dont "guess" the distance, get a tape measure. cheap as chips. come on man!
 

budman678

I come from the land where the oceans freeze
Veteran
e8jUC.jpg
 
G

grassott

^ she dont look that "nasty", she looks like she'll give you dank bud if you do things correctly. she needs a tad more nitrogen and take care when watering/feeding. you see the lower leaves looking most effected? i think thats because when you water/feed, the bottom leaves are getting splashed. try not to hit the leaves whilst watering. oh, and make sure your ph is correct too and you'll be ok.
done the hand test yet?
you mention you have younger plants which would probably be shorter. at this stage prop up the smaller plants on books or empty boxes or something to get the top canopy nice and even. peace dude.
 

budman678

I come from the land where the oceans freeze
Veteran
this is my first run from seed, second run ever and i am amazed out how bushy this seedingling is. i mean, good lord! it is so tight and busy its hard to get in there and see the main stalk. this is some critical +
 

budman678

I come from the land where the oceans freeze
Veteran
i am about 24inches from the canopy and its not too hot. i know they take a little more heat during veg so i am not going to worry too much. we have some fans circulating air although i havent turned on my inline fan/scrubber because i dont think its needed.

there is no smell and the tent is wide open so they are getting a lot of good air flow
 

budman678

I come from the land where the oceans freeze
Veteran
im about 16-18 inches from canopy. temps top out at 81f. not too bad. things are looking good. going to really starting bending on the oldest femals. critical +. see what she can do. the other sd kushes are fem'd
 

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