Why is this so....

[Gaytimegrower]

Hi guys,

Can any one tell me what is wrong with this plant?

It is sitting next to one that is looking quite healthy. Both are on the same nutrient feed line.

Details are:

Seedlings 2 weeks old

ph 5.5,

nutes 10 ( 700 ppm ). original water cf 3

Temp. above plants 25 - 30 deg C,

water temp 25 -26 deg C.

Using expanded clay in a recirculating system.

Pump on 15 mins every 3 hours.

 

Any help appreciated.

[Gaytimegrower]

Next pic shows the difference in size of plants.

When I compare my plants to ther pics on here, I notice they dont have that nice deep green healthy look to them. What the f--k am I doing wrong?

[Tam]

I am no expert but maybe they are yellowish because they are not getting enough oxygen, or they have root rot or some other root problem… K2 1 looks like it might have a root rot problem to me. Have you been misting them? Are they getting enough nitrogen? You have your pH much lower than me, I keep mine around 6 – 6.5 in deep water culture, others I have read keep it even higher.

 

Just my 2c worth.

 

regards, Tam

[Tam]

okay so pH may not matter that much.

 

"pH

 

pH is a scale from 1 to 14 that measures acid-to-alkaline balance. One is the most acidic, 7 is neutral and 14 is most alkaline. Every full point change in pH signifies a 10-fold increase or decrease in acidity or alkalinity. For example, soil or water with a pH of 5 is 10 times more acid than water or soil with a pH of 6. Water with a pH of 5 is 100 times more acidic than water with a pH of 7. With a 10-fold difference between each point on the scale, accurate measurement and control is essential to a strong healthy garden.

 

Cannabis grows best in soil with a pH from 6.5 – 7. Within this range, marijuana can properly absorb and process available nutrients most efficiently. If the pH is too low (acidic), acid salts bind nutrients chemically, and the roots are unable to absorb them. An alkaline soil with a high pH causes nutrients to become unavailable. Toxic salt build up that limits water intake by roots also becomes a problem. Hydroponic solutions perform best in a pH range a little lower than for soil. The ideal pH range for hydroponics is from 5.8 – 6.8. Some growers run the pH at lower levels and report no problems with nutrient uptake."

 

pH, Excerpted from Chapter Three, Indoor Marijuana Horticulture, The Indoor Bible

 

have your tried TLC?

 

regards, tam

[pipeman]

PH of 5.5 sounds about right to me, you could maybe try to raise it a bit, not much past 6.0 though. Have you calibrated your PH meter recently? They do need it from time to time. Are you able to test the CF of your runoff? That will tell you if you got nute lockout problems. Your other plant is showing signs of trouble too. Try giving them a flush of PH adjusted water and starting again with weak nutes. Measure the CF of the waste water to see if the plants are aborbing nutes. A buildup of a single trace element can cause nute lockout.

[Luke Skywalker]

Your water temp could come down a couple degrees. You can do this with a frozen water bottle placed into the reservoir.

 

These are all seed plants, yeah? And they're from proven stock? I mean, is it a reliable and reputable seed company and strain? I ask because there can be large differences in plant size/growth/potency between the seeds grown out from the same cross. You can get some strains which will produce fairly uniform plants, with minimal variation between each plant of that cross, but others are wildly variant, throwing up short and tall, potent and weedy, all kinds of different plants. Now, I'm not saying this is necessarily your problem, but it's one possibility. The seed stock is crap.

 

Ok, eliminating genetics, you could have a few probs... what's the ph level in the runoff from the pots?

 

Oh, and tam, ph levels required to maintain soil biota are different to those best applied in hydroponic systems. In a soil grow you're effectively feeding the soil, rather than the plants. These soil biota are responsible for converting the nutrients present in the soil in the form of either salts or organic compounds, to the usable plant forms which can be absorbed by the plant and help it to grow. In hydroponics there are no biota, (unless you add them...) and the pH levels are needed a little lower. This is because you are feeding the plants directly with plant available nutrients in solution, and these are in their most readily absorbed forms at around the pH level of 5.5 or so, perhaps even a couple points lower. If you do a search on the boards, or perhaps in the growfaq, you'll see a comparitive nutrient availabilty of soil and hydroponics at different ph levels.

 

Aaaaanyway, back to you GTG, I'd have to say that it's also possible that the plants need more regular irrigation. 15 mins every 3 hours isn't really that often for a pure expanded clay media. Try upping that to 15 every 2, and yeah, flush the pots all out with ph adjusted water, and then reformulate the nutrients in the tank. You won't see any recovery in the burnt tissue, but if it's an underfert or ph imbalance issue, then you should quickly see the plants perk up and get greener. One more, what's the humidity like in there? Just out of curiosity...

 

There are a few other possibilities, but until we've got a little more info from ya, we'll just see if the ones we will be suggesting are likely causes. Hope that helps mate.

[Guest Wilderbud]

What sort of nutrients are you using?

[Brainstorm]

the three seedlings pictured all show signs of problems, what are the seedlings like in the other pots?

 

Without being able to see the true colour the leaves are it is hard to diagnos what the problems may be - try taking pictures without your grow lights on using just your flash to light the plants.

 

I would try the advice already offered but you may have to water more often than Luke has suggested (try his watering solution first though as overwatering can be bad as well) as the expanded clay balls don't really hold much water.

 

Also see if you can get the temp above the plants down to between 20 to 25 degrees. they don't really like temps around the 30 degrees and above, in areas like qld this can be hard to achieve though without a fair bit of effort.

[Gaytimegrower]

Okay guys, this is what is happening.

 

Earlier today, I put the pump (1000 l/hr ) into 60 litres of ph adjusted water ( 5.5).

The ec was my normal tap water of cf 3 - 210 ppm.

Temp 24 deg. C

 

I flushed till each pot was flooded and then re-flushed a couple more times after that. I took a reading of the water:

ph had gone to 6.5

cf 5 - 350 ppm

 

I thought I may maintain using this water for a few days, giving it 15 mins on and 2 hours off as recommended above. What do you think?

 

Now to answer some questions:

Ph meter is calibrated

2 week old seedlings,some are different sizes, not the best looking specimens.

Humidity is 40%

 

i am going to bore you here as I have turned the lights off and done a few shots. Got me completely stuffed guys.

 

Any help at all would be great.

[Gaytimegrower]

This is the plant next to the dunnoo plant.