Any Ideas?

[TriIron]

How long has this problem been going on? 30 Days
What STRAIN are you growing? Gubal
What was the establishing technique? (seed or clone?) Clone
What is the age of your plants? 45 Days
How Tall are the plants? 6-8 Inches
What PHASE (seedling, vegetative or flower) are the plants in? Veg
What Technique are you using? (SOG, SCROG etc) Neither Yet.
What size pots are you using? (Include how many subjects to pot) Currently they are in .5 gallon pots
What substrate/medium are you using? What brand of soil mixture are you using?(percentage of perlite, vermiculite...etc?) 75% ACE Organic Soil 25% Perlite
What Nutrient's are you using?How much of each with how much water? How Often? *Knowing the brand is very helpful* Botannicare Veg, I water every 3-4 days, every other watering with 5ml/gal.
What is the TDS/EC/PPM of your nutrients used? Don't Know
What is the pH of the "RUN-OFF"? Don't Know
What method of pH test was administered? Using Strips? pH pen? I PH the water with the liquid drops
How often are you watering? 3-4 days
When was your last feeding and how often are you feeding? 3 days ago
What size bulb are you using? T-5
What is the distance to the canopy? 12 Inches
What is your RH Factor? (Relative Humidity) 15-20%
What is the canopy temperature? 81-84
What is the Day/Night Temp? (Include fluctuation range) 84day/72night
What is the current Air Flow? (cfm etc.) Fan circulating air, room air tight
Is the fan blowing directly at plants? yes
Is the grow substrate constantly wet or moist? no
Is your water HARD or SOFT? Hard
What water are you using? Reverse Osmosis (RO)? Tap? Bottled? Well water? Distilled? Mineral Water? Tap
Has plant been recently pruned, cloned or pinched? Some pruned, some not
Have any pest chemicals been used? If so what and when? No
Are plant's infected with pest's? No


Hmm, won't let me upload pics to my gallery to put online. What seems to be happening is the new growth on my plants are nice and green, but the lower leaves are yellowing from the veins and then turning brown at the tips. I always tend to err on the side of not giving enough nutrients rather than too much, and on average they receive food once a week. Humidity is a little low 15-20%, but in the climate I live it is tough to keep it higher.

 

[Pirate138]

Prob a N deficiency.

 

[stinkyattic]

T5s need to be much closer to the canopy. How many are you using?
Check your runoff number- that's important.
Your humidity is quite low and your temps are slightly high; you should be running a nice roomy pot and giving as much water as the plants can use, while still allowing for some drying between waterings.

 

[TriIron]

Here are a few pictures of the plants. I can get some closeups if need be for anyone's diagnosis.

 

[stinkyattic]

Magnesium locked out by improper pH. Looks like peat-based soil. Foliar feed with Epsom salts dissolved at 1/2 teaspoon or so per quart of tepid water with one drop of dish soap. Mist lightly, allow to dry. Repeat daily until you see greening.

Also fix the conditions that caused lockout. Your pH is probably too low. Get a tester kit and check the runoff. I'll bet it is around 6. You'll need to flush with about a gallon per pot of tap water adjusted to pH 7.2 if that is the case, and finish with a feeding of 1/2 strenght complete grow fert at pH 6.8.

The hardware store brand potting soils I've seen are all based on the promix model- Peat, perlite, and lime. They are good in the pot for between 4 and 8 weeks before showing pH drop from the lime being used up. This length of time is determined by the hardness of your water, the pH of your water, and the presence/absence of organic acids in the water. To minimize stress on teh plant, start in small pots and just re-pot up to slightly larger sizes every 6 weeks, so that new roots always find fresh soil. Monitor your runoff pH and adjust the pH of your fert solution if necessary.

 

[limey]

Definitely, definitely a pH/nutrient and, by the looks of things, you are going to have to act fast to save these plants.

I agree with stinky here...

Flush these plants really thoroughly under a tap/shower to make sure you have rinsed out any salts in the soil

Pop down to your local aquarium centre or growshop and buy yourself a good electronic pH pen/meter and some calibration fluid.

As stinky says, "finish with a feeding of 1/2 strenght complete grow fert at pH 6.8". You can go down as far as pH 6.5

Monitor the pH of the run off for a few days, to check you have a stable pH in your growing medium of about 6.5.

best of luck, mate, but act fast!!

 

[stinkyattic]

If it turns out that your pH really was way too low, I actually like to water at the high end of that range to give myself some time for it to drop again before dropping right back down outta range, lol! But yeah, limey's right, 6.5 is still acceptable.

 

[TriIron]

Ok, well I flushed them good with distilled water, and ran epsom salts through them as reccomended. I still am having a problem with some of the plants. I found the probe to my PH/PPM tester and got it working and here are the numbers:

Tap Water: 7.4
Tap PPM: 445

When I ran 7.4 PH water through one of the plants that is struggling more than others, the runoff was 7.0 and registered an error on the PPM. (not 100% sure I have the PPM calibrated right, but will cover that later). I then adjusted my tap water to 6.2 PH and watered another problem plant. The runoff came out at 6.7, so I watered all my remaining plants with that.

I have the Hanna Instruments PH/TDS/EC/PPM tester. Calibrating the PH is self explanatory. For the PPM, I used cleaner on it, rinsed it, and submerged it into GH Standard Reference Solution 25C. It says 1500 ppM (NaCI scale) which I assume is the scale I should be using. With the probe dipped in the solution for about a minute I adjusted the knob until it read 1500. Right after that I tested my tap water at 445 ppm. Seems high to me, but the concerning part is that the runoff seems too high for it to register a value. I don't overfeed my plants, if anything I am guilty of underfeeding a little.

 

[TriIron]

Lo and behold I check the mail and find that I got my water summary. They say my PH is 7.8. I am also drinking contaminated water. How nice.