First grow 400w MH/HPS Day 15, pics, need help

Hello Rollitup, I'm new to the Cannabis scene and decided to grow my own because the prices here in Arizona are ridiculous.

Lighting:
400w MH for veg 24/0 (Was at 18/6 until Day 10)
400w HPS for flowering 12/12

Humidity:

Fluctuates between 20% and 30%


PH:

When testing the water, it looks to be about between 6.0 and 6.5
I have no ability to test run off as soil comes out with it, skewing the ph indicator solution's color


Soil:

Scotts Premium potting soil from Lowe's (THERE IS NO FOX FARMS WHERE I LIVE, BELIEVE ME, I LOOKED)

Temperatures:

The first week, the plants were on an 18/6 cycle, but the grow room was getting down to about 60 degrees at night, so I switched to a 24/0 cycle on Day 10 in an attempt to boost photosynthesis and control cold temperatures, and since then, temps have stabilized between 70 and 80 degrees, usually about 75-78 degrees.


Dates Planted:

Germinated the seeds on Dec 11th, and planted on Dec 14th.



Concerns:

Seedlings are currently on Day 15. They grew at a decent rate for the first few days, but have since slowed to not much growth at all. I am worried about their growth rate, and looking for remedies to speed their growth. They seem to be stuck in their current state of growth. In one of the pictures below, you can see brown tips on the leaves, and in general, most of them are not fully green, but slightly yellow, not sure what is causing it and am looking for some help. the DQ cup is an attempt to test a makeshift humidity dome on one plant that is lagging behind the rest be a large amount.

I expected much more growth than I am observing, and since I have never grown before, I am not sure what the average size is at 15 days, but I imagine it is more than I have.

a mix of high light intensity, low humidity. don't worry much, i would put some fluros over them for some time. sometimes they seem like they freeze, but theyr building root structure, not much foilage to support dry enviroment and heavy light. make sure not to overwater, and be patient

A humidifier is on the way, with humidity increased to about 45%, would I still need to switch to fluorescents?

at least for some time till they start growing leaves, mh is not helping at this stage

Is there an average size of plant at which you can begin using an MH bulb? I thought the only thing to worry about was temps and they never go above 80.

no average size, just wait till you see the seedlings growing in size then give em the mh light.

Does ur soil have any ferts in it if so that might be why they are yellow , don't wanna give any ferts till second or third wk. thats my thought anyway

You've probably already stunted your plants with the low humidity and the MH they weren't strong enough to tolerate, and although you didn't mention it, you may be nuting way too soon (or about to)......... But with that being said, stunted plants can recover and still provide some bud. Just glad you didn't as "guess at my yeild"...........

The soil comes with slight amounts of nutes in them, but I was not planning on adding nutes for a while because of that.

I have killed 5 plants with soil that had ferts in it gets a little costly buying fems. I would get some superthrive or any of the root stimulators and give them a little. I won't grow without them its unreal the difference it makes just overnight you can tell . I've found it in walmart couldn't believe it !! Good luck

Switched to 18/6 lighting. Will post back with pictures of results.

Day 19

The leaves are starting to turn brown around the edges, and in the center of some leaves. Pics attached, I hope you guys can help. Temperatures dropped to 56 degrees one night, and got it stabilized with a heater the next day to a minimum of 68 degrees, however the growth of brown spots has continued over the past two days.

Are you spraying them with anything ? Still looks like its nute burn maybe not if you are sraying them and the water is making burnt spots from the light I try to spray under the leaves but I don't usually do that to seedling

No, not spraying, haven't watered in 4 days.

did you switch to fluros? humidity in check? babies need tenderness, dont let them dry or drown, just moist and airy. good luck

Day 20

Gave some h2o2 and 1/4 strength foxfarm big bloom to two plants each. Watered other four.

Hey, I'm back, so in the time i've been gone, all of them have survived, they were transplanted to two gallon pots about 8 days ago, I can say about 8 days ago they looked roughly the same as they did in the last set of pictures. They were transplanted to two gallon pots with FFOF, superthrive, and big bloom.

Since then they have actually begun to grow. This is why you don't use Scott's soil I guess. If anyone sees this thread, be sure to get the fox farm, you'll wish you did if you don't. Here are some pictures to go off as well.



Also started were some new plants, from the same bagseed, this time, these gals were in a stable atmosphere from the start. They were started in bark plugs inside a humidity dome with 124 watts of CFLs above. 3 days ago they were transplanted to 2 gallon pots but remain under CFLs only.

On Top Day 17

On Bottom Day 42

zem said:

did you switch to fluros? humidity in check? babies need tenderness, dont let them dry or drown, just moist and airy. good luck

Click to expand...

flouros are not a must.ive always used mh from start to finish of veg always.
it looks more like a problem with the medium.perhaps too rich for seedlings.

i use plagron light mix from start to finish,but fox farm is good stuff too i hear.your babys are looking alot better.they should make a full recovery now.happy growing,peace.

Time for an update, it's been 11 days and the new plants are on day 28 and the older ones are on day 53.

Added some more 26 watt CFLs and moved all the plants together under the metal halide.


The two in the front middle are the new ones.