Yellowing on 3 week olds

[willowgrow]

My setup:

6 Plants; 3 are 3 weeks old (group A); 3 are newly planted, 2 have sprouted so far (group B).

Group A are in FF Happy Frog soil and are seeds I found in a bag of 50 bud.
Group B are in FFOF and are 2x Chrystal 1x LA Woman from Nirvana (fem'd)
All 6 are in 5gal pails

Lights: 600w Aircooled HPS - 18/6 light cycle

Temp: Room temps stay between 70-83 F, the lights about about 8" from the plants with a fan blowing the air between.

Been just top feeding the plants with straight tap water (pH around 7)

About a week ago the temps shot up to 103F but I have since solved the problem and they haven't risen above 83.

All 3 of the plants in group A have pretty much stopped growing, and are yellowing, I only had time to post 1 pic but they all look like this and im not sure why; so hopefully you guys can lend some insight. If i forgot to add something let me know, ill post more pics later (gotta get to class )

Thanks!

 

[willowgrow]

here is the whole setup

 

[Alistair]

It would a good idea to water with good water, pH about 6.5. I wonder if you plants like the tap water? If not, then reverse osmosis water is recommended.

You're using good soil, so that shouldn't be a problem, unless it doesn't have enough organic nutrients in it such as nitrogen. Assuming the pH is within the proper range, then perhaps, you need to start feeding them.

I don't really know, I'm just throwing some ideas out there. So far, they look pretty healthy, except the yellowing.

 

[HippyInEngland]

Your soil looks bone dry.

eace:

 

[purplephazes]

Hi there yup bone dry for sure ! And around 7 ph is great.... 6.8 precisely ! Because around 7.3 ph is locking out the trace elements ! Doe's your ph meter need calibrating or do i need your tap water ? Tak car ! To perfect water !

 

[Hick]

Your soil looks bone dry.

eace:

yup.. and in addition, I can see where you've attempted to only lightly water, directly around the plants. IMO/E, it's better to water deep and thorough, until runoff. Then allow it to dry out well before watering again.
There in lies the problem associated with small plants in large containers. It makes gaugeing 'proper' watering nearly impossible.

 

[willowgrow]

Thanks for all the responses! This is my first soil grow( dwc last go around ) and I always second guess myself on watering. So just water slowly and thoroughly till it seeps out the bottom? And I plan on starting FF 3-part Jutes on the bigger ones today

 

[purplephazes]

I would recommend only 1/4 strength nutes to begin with and then slowly increase the amount ! Take care !