Brown Spots On Seedling Leaves

Strain: Bison Breath (Greenpoint Seeds)
Tent: 20”x20”x48”
Light: Mars TS1000
Soil: Fox Farm Ocean Forest
Current Pot Size:
Ventilation: 4” Exhaust Fan with Carbon Filter - 6” Desk Fan
Temperature: 81 F
Relative Humidity: 45%
Age: 8 Days
Water has been PH'd to 6.5

This is my second grow and I am trying to rectify all of the mistakes I made the first time around, better soil, better lighting etc. Both plants are growing well and look to be pretty healthy however today I noticed brown spotting on the leaves of one of the plants. I really do not want to run into the same issues I had on my first grow. Any help is greatly appreciated!

6 inch desk fan and 4 inch inline in a 20 x 20 - Your problem is wind, plants hate it they just like good air exchange.

Fix this and you be fine

They look fine . FFOF can at times slightly shock some seedlings ( from being a “ hotter “ soil ) BUT they grow out of it.
They will acclimate ( as long as you don’t dump more things on top ) at this stage. You are probably getting to the point of transplant anyways ( roots have hit bottom and may started to circle ) , so even when you up pot into larger container of SAME medium it will already have been accustomed to medium .

Stay the course with the medium as is. Let your plants continue their rooting in larger pot on just the water.
FFOF will feed for weeks. This way you can concentrate on the air exchange issue in your space as stated.

Budzbuddha said:

They look fine . FFOF can at times slightly shock some seedlings ( from being a “ hotter “ soil ) BUT they grow out of it.
They will acclimate ( as long as you don’t dump more things on top ) at this stage. You are probably getting to the point of transplant anyways ( roots have hit bottom and may started to circle ) , so even when you up pot into larger container of SAME medium it will already have been accustomed to medium .

Stay the course with the medium as is. Let your plants continue their rooting in larger pot on just the water.
FFOF will feed for weeks. This way you can concentrate on the air exchange issue in your space as stated.

Click to expand...

Awesome, that is what I hoped was the cause. My last grow I went on vacation and came back to a serious CalMag deficiency then overfeed Nitrogen in bloom causing foxtailing and I just want to ensure that I correct any issues as soon as they are spotted. Will I be okay going from the solo cups to the final 3 gallon fabric pots or should I jump up to 1 gallon pots first? Thanks for all of your help!

Kingrow1 said:

6 inch desk fan and 4 inch inline in a 20 x 20 - Your problem is wind, plants hate it they just like good air exchange.

Fix this and you be fine

Click to expand...

Thanks I turned the fan that was blowing up at the light off and am going to leave the inline fan on to see how it goes. Maybe it is time to remove the driver from the light and place it outside the tent so I do not need as much air flow. Thank you!

@Kingrow1 is correct about wind, but enough air movement to make plants dance is perfect. When they are larger, and you’ve trimmed the under canopy, that’s a great place for air movement, and also above the canopy. Not like palms on the beach. Just a hint of movement is ideal

Just leave them alone and let them grow. One of the biggest mistakes new growers do is panic over a spot here and there. The plant is not going to be perfect.

Father Ramirez said:

@Kingrow1 is correct about wind, but enough air movement to make plants dance is perfect. When they are larger, and you’ve trimmed the under canopy, that’s a great place for air movement, and also above the canopy. Not like palms on the beach. Just a hint of movement is ideal

Click to expand...

The fan was facing directly up on low so all of the movement was from the air hitting the light then bouncing back, I didnt think it was very strong but could be wrong. Last grow one of my plants had no fans for the first month and the plant could barely support itself. I will definitely be tweaking it though and maybe I should put it on a timer with the lights so it's not 24/7. Thanks so much for the help!

xtsho said:

Just leave them alone and let them grow. One of the biggest mistakes new growers do is panic over a spot here and there. The plant is not going to be perfect.

Click to expand...

I know, may be a little more worried because of issues last grow I just feel like I need to catch things early. My tent is small and I can really only grow 1 plant so messing up and getting a less then ideal end product is depressing. Last grow I got 8oz dry but it was foxtailed and not very potent. I will definitely try to not worry about everything though. Thank you!

Jelimafish said:

The fan was facing directly up on low so all of the movement was from the air hitting the light then bouncing back, I didnt think it was very strong but could be wrong. Last grow one of my plants had no fans for the first month and the plant could barely support itself. I will definitely be tweaking it though and maybe I should put it on a timer with the lights so it's not 24/7. Thanks so much for the help!

Click to expand...

That’s precisely why we use fans

xtsho said:

Just leave them alone and let them grow. One of the biggest mistakes new growers do is panic over a spot here and there. The plant is not going to be perfect.

Click to expand...

I am trying to be patient however the bottom leaves seem to be getting worse. I am going to go pick up some perlite and maybe some lime to amend the soil prior to transplanting. Since the new growth looks pretty good I am hoping this is just the seedlings adjusting to their environment but it is quite possible I am doing something else wrong. The only thing that I can see that is less then optimal is the RH but I do not know if that can cause these leaf symptoms.