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mebintx
07-28-2009, 12:47 PM
First timer here Just noticed one of my four 12 day old plants is yellowing from the top center- 3 rd set of new leaves are yellowish and the older 2nd set of leaves just below it are yellowing from the stem and radiatiing out. The others look fine right now. (see pictures of sickie and 3 healthy sisters) Set up 2 100W CFL with Y adaptor in Brooder reflector one per plant about 2-3" from top of plants

4) Is there a consistent fresh air supply? yes
5) Do you have an exhaust fan and a circulation fan? just circulation fan have AC on to bring in new air
6) What are the bulb wattages, kelvin ratings, and schedule? These are daylight, 100W CFL in the 6000 range on 24x7

Your medium:
.7) Specific brand and type of soil, using Fox Farm Ocean Forest
.8) Size of container 1qt - for these 12 day old seedlings - only one of the plants is showing this - other 3 look good
.9) Did you use peat pucks (or similar) to root clones or germinate seedlings? no - generated in paper towl and replanted

Your nutrients and water:
10) Source of water? (tap, bottled or filtered) - Filtered tap What's it's ph before adjusting? just checked for the first time thinking i might be having a PH problem and it is 7.8 - although city website says tests done in 2008 ranged from 8.0-8.3

11) Method of checking water ph. my pool test kit
12) Method of adjusting water ph. (phosphoric acid, white vinegar, hydrated lime, PH Up...) - none yet - was letting chlorine dissipate for a couple of days

13) Specific brand and N-P-K ratio for each bottle. List dosages (quantity per gallon) and current feeding schedule. Fox Farm Grow Big Liquid Plant Food (6-4-4) - was using about 1/3-1/2 strength - began feeding about 4 days ago

14) How often are you watering between feedings, and how much per watering? was just giving water with nutes each time - watering with this about every other day when the soil feels dry about 1-1.5" deep - drenching until water runs out
15) Any additives or tea's? (Superthrive, CalMag, molasses, Mother's Earth...) None
16) Are your ph levels stable, or do they fluctuate? uncertain
17) What is your ingoing water's ph? 7.8 ...your runoff ph? haven't tested yet as will need to water
18) Do you foliar feed? If so, with what, how often, and at what time do you spray? Not yet

Your growroom:
19) Indoors or outdoors? Indoors
20) What size of closet 2x2x8'
21) What are the temps and humidity levels while lights are on? temp 85-90 and humidty about 40-50% ...With lights off?
22) Have you seen signs of insects in the growroom? nope

Your strain:
23) What strain are you growing? mostly indica
24) From seeds or clones? seeds
25) Is this an autoflower strain? not to my knowledte
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crabbyback
07-28-2009, 01:55 PM
City water supply is NEVER consistent, no matter what they say. :wtf:
Always test your tap pH. If needed, adjust either up or down to the soil range of 6.3 ~ 6.8. You may find with experience, that it doesn't vary too much, or that it stays in the correct range. But, I would caution you, test it each time.

Your Fox Forest Ocean Forest soil is extremely rich. Many, many people burn their seedlings into oblivion with this stuff. Even without added nutes, so be really careful. Looking at your pics, plants look great, I really can't see any issues. Just be so, so careful when you add nutes and do it slowly (1/4 strength, then 1/2, etc...)

Edit: They are very dark green. May be overfeeding a bit. Cut back on those nutes and adjust your pH.

Rusty Trichome
07-28-2009, 09:35 PM
Ph is a big issue that you will need to address. My wellwater is 8.0ish, and I adjust using General Hydroponics phDown. (phosphoric acid) A little goes a long way, and no adverse effects. The higher your water ph, the quicker the buffering (usually lime, added by the manufacturer) in the soil depletes, and the big problems start.

I agree with crabbyback. ixnay on the utesnay. FFOF has the necessary nutes for the first month or so, and then ease into the nutes per the schedule. I know the specs on the FFOF mentions to add the Big Bloom...but with the ph stress, might be a good idea to wait on adding more BB for a week or two. (or until the ph issue is resolved)

mebintx
07-28-2009, 10:51 PM
I did some trials today using white vinegar and about 1/2 tsp knocked my tap water down to about 6.8 - so, I'll use this from now on. I think the combination of adding the nutes and high pH H20 was starting to have an effect. So, it's back to no nutes for a couple more weeks and pH adjusted water for me!

fourkicks
07-28-2009, 11:11 PM
what ph do you guys go for..i read on this site aim for ph6..is this not right...is my ph too low

Rusty Trichome
07-29-2009, 12:43 PM
what ph do you guys go for..i read on this site aim for ph6..is this not right...is my ph too low
It depends on what medium you use.
With normal (peat based) potting mixes, water ph should be between 6.3 and 6.8.

fourkicks
07-29-2009, 01:36 PM
IM USING BIO BIZZ BIZZ ALL MIX AT THE MOMENT,BUT I M GOING BACK TO GOOD OLD PEAT MOSS ,PERLITE AND VERMICULITE FROM THE NOW ON..I FIND IT DRAINS BETTER.. THE PH 6 I HAVE BEEN USING IS PROBABLY TO BLAME FOR THE SMALLER BUDS IM GETTING ON MY SECOND GROW.MY FIRST GROW WAS ALOT BIGGER FOR THE SAME AMOUNT OF PLANTS..THANKS RUSTY YOUR A STAR..6.5 FOR ME ALLL THE WAY NOW

Rusty Trichome
07-29-2009, 02:18 PM
...I'd aim for a ph of 6.8ish.

Are you mixing your own potting mix? If so, you'll have to either add something (lime) for ph buffering, or keep a very close eye on your runoff ph. (peat has a very low ph)

Commercial peat-based potting mixes are usually pre-buffered, and are the easiest to use. Commercial compost mixes can vary widely in ph, but are generally in the 6.0 range, which is way too low for cannabis indoors in pots, and needs shitloads of lime and perlite added.

If mixing your own, there should be a recipe or two available. Use the site's search function, likely you'll stumble across 'em.

Next time though, try starting your own thread, and quit shouting at us. :thumbsup: