Droopy Leaves + Brownish Spots

[kanvict]

Using a 400w MH bulb 12 inches away from my plants in a tent with a 190 CFM fan exhausting air every 15 minutes and an intake fan at the bottom circulating air as well (I'm in the beginning stage of veg so don't run the exhaust 24/7 as my room is already properly ventilated). Few days ago, I noticed some brownish spots on my bottom leaves but the new leaves looked normal... than the leaves were really droopy even though I hadn't watered them and now the new leaves are starting to develop brownish spots as well. I can't figure out if this is light burn, heat stress or a nutrient burn somehow (people say Fox Farm Ocean is too hard for seedlings).

Humidity in the tent is maintained around 35-55% (mostly around 35%) with temperatures ranging from 66 in the night up to as high as 88 during the day time. Oh and the plants are in 3 gallon smart pots being watered with tap water (no chloromine). Really hoping to figure out what's wrong with this plant and save it before it's gone. Thanks guys!

 

[CronicHempHog]

is it ffof?
I know for rooted clones is fine
but if its from seedling I would mix it with at least by half with something weaker or inert
just enough for a cup and let it grow out a bit in the cup then transplant it to the smartpot
by the time you transplant it should be able to handle the ffof
one of my clones is in a 2 gallon airpot with ffof in bloom haven't added anything but plain water for watering
but I let it get well rooted in the cup first but it wasn't a seedling it was a rooted clone in straight ffof.
so yea you might be getting some nute burn on seedlings with ffof, also should have let it root in a smaller container first
just wait it out lots of plain water

 

[kanvict]

Hey thanks for the reply man, its hard finding someone to actually help. By saying add a lot of "plain" water, do you mean straight tap water with a pH 8 (since FFOF Zis slightly acidic I hear) or flush/water with RO water?

 

[CronicHempHog]

I just use tap where I live the water is fine out of the tap but everywhere is different
you might be better off with ro water where you live I don't know of the water quality
where you are
I guess if the soil is slightly acidic a higher alkaline water or higher ph should be fine
im gonna assume. I never heard of ffof's acidity only knew it was a little hot for seedlings
its what I hear all the time, but as ive used it for rooted clones I know its fine for them
as they are not seedlings.
but yea where I live I use plain tap out of the faucet didn't show any deficiency's yet

 

[kanvict]

You think I should flush the seedling with RO water to get rid of any nutes that may be burning the plant? The new leaves are starting to get worst and worst... really considering flushing with RO water as I can't see what else could be causing this.

 

[CronicHempHog]

I don't think its added nutes if its just the ffof soil
it would be the mix of the soil
like bat guano or worm casting whatever they may have mixed in
don't think youll be able to just flush it out
you could give it a try tho but things react slower in soil I don't know if id rush to flush
just keep feeding it ro water or if the tap is good where you are I don't see why not use that either