Seedling growing slowly and leaves yellowish with brown marks

[tencents]

Hi,

I recently transplanted a seedling to a bigger pot and since then it has turned a yellowish green with some brown marks on it. I originally planted 2 in a coco and perlite mix and neither grew very well, which I thought was because of the coarse coco, so the new soil is a germination mix from my local nursery. The one, which was really struggling before the transplant, died and now I am having issues with the other one.

From some research I think it may be one of the following:
1 - Stress from the transplant (has been nearly a week though)
2 - Fungus gnats (I've been on leave so I have been putting my plants outside in the sun as I am concerned my lighting is insufficient)
3 - Some kind of nutrient deficiency

Any advice would be greatly appreciated.

Attached are some photos, sorry about the poor quality, I just couldnt get a high quality photo with this phone.

[oldjarhead100]

hey tencents heres my two cents (sorry couldn't resist) coco has no nutes in it if you plant seeds in it you need to start giving nutes very weak nutes I will mix nute for 1 gallon with 6 gallons of water to start and every week increase the amount of nutes . what was the type of water (tap,ro ) what is the ph my tap water is 7.3 I have to lower it to 6 every watering but it makes a huge difference in how fast the seedling feed . I only give the seedlings about a pint of water to begin with then check with my meter to see when they need more (usually 1 or 2 days). if you give to much water then they can get root rot and die. I hope this helps read the tutorials on gwe Nebula's far more knowledgeable and articulate than I am

[tencents]

Hey ojh. Tx for the reply, I think maybe that was one of the mistakes I made when I planted in the coco mix. I used tap water and it is very alkaline, like 9! but I PH it down to around 6 for watering's. I transplanted them into a soil mix now, and the new ones I am growing in the mix seem pretty happy except for the one I transplanted, its going yellow with brown marks and I don't know why? I'm hoping its just stress from the transplant and it will recover on its own but I'm worried its not and if I leave it it will get worse and die. Even the new leaves have brown marks. I've been reading the GWE posts, thats where I got the info for above it just seems it could be many things and I'm not too sure which it is?

[oldjarhead100]

it may take up to two weeks to recover just give her some tender care and see.

[Minoo96]

If you can, set up a rain water harvester. (a drum at the end of a rain gutter for instance.) water from a well is the best. Water after a thunder storm is also very good (cannot explain it, it's a grand-ma's trick and she knows what she's talking about, she's is the kind to make her own blood meal when she cook one of her hens). If you do not have access to any of those, I recommend mineral water. If even that is unavailable, you should try to filter your tap water. (with a "brita" like filter for instance.)

[tencents]

We heading into winter now so rain water will be hard to come by but we get plenty of thunder storms in summer so I'll keep that in mind, tx. I will look at getting some mineral water for now. I have a water filter in my fridge, do you think that will be good enough?

[Minoo96]

It'll always be better than simple tap water, or at least it should be. But go for mineral water, you will be sure that you're not giving anything bad to the plant. (basically they put chlore in tap water to filter it, you can imagine the amount of damage it can do to a plant.) now if you live in an area where tap water is not filtered (I used to live in such a place in India) you might be able to use it. (I had a well, so I never used city water. My water tank for the house was filled using well water.)

[Minoo96]

Also, what's your setup? The slow growth could be because the sun/lamp isn't strong enough. I have also stunted seedlings (with autos -_-') and its mainly because I do not get enough sun. Germinated them too soon, it's still cloudy half of the days here. (growing outdoor, but germinating inside, "near a window")

[tencents]

Here is my setup, I have also been concerned about the amount of light but I am on leave at the moment so I have been putting them out in the sun during the day, we out of summer but the cold hasn't hit yet so its a warm sun but not too hot.

Setup:
- Growing in a grow tent
- CFL lights, 1x65W (6400K 3600lm) & 1x45W (6400K 2600lm)
- Germination mix from local nursery (nice and light and fluffy) - worked well with my veggies
- Humidity ranges between 60 and 80%
- Temperature is around 25 deg Celsius
- 18\6 light rotation