First Grow, Sulfur Deficiency?

[flossdaily]

Hydro grow

• Are you growing from seed or clones?
  • Seeds
• How old are your plants?
  • About three weeks. Oct 1 had first signs of sprouts in my 1.5" cubes
• How tall are your plants?
  • 8 or so inches
• 4. What type of hydro system are you using?
  • RDWC, ~25gallons total, loads of oxygen. Four pots inside tent, small res outside
• 5. What brand/type of nutrients are you using?
  • General Hydropnics three-step. Currently on day four of full-strength "aggressive veg"
• 6. What is the Ph of your nutrient solution?
  • Waiting for digital meter, but based on color, about 6.0 on the nose
• 7. What is the PPM/EC of your tap water?
  • 10-20, it's RO water
• 8. What is the PPM/EC of your nutrient solution?
  • 205ppm
• 9. What is the temperature of your nutrient solution?
  • 73F
• 10. Does your PPM/EC show a rise or fall when you do your daily PPM check?
  • Doesn't seem to change as of yet (plants are still too small I think?)
• 11. Does your pH show a rise or fall when you do your daily check?
  • Same as above
• 12. Do you foliar feed or spray your plants with anything?
  • Nope
• 13. What kind of lights do you use and how many watts combined? (HPS, MH, fluorescent, halogen, incandescent "plant lights")
  • LED, "King Plus 1500w". I have two, they've both been on but with both on I have heat issues. So I'm back to one for now.
• 14. How close are your lights to the plants?
  • 22" off the top
• 15. What size is your grow space in square feet?
  • 4' x 4'
• 16. What is the temperature and humidity in your grow space?
  • ~80F, 40 or so RH
• 17. Have you noticed any insect activity in your grow space?
  • None
• 18. How much experience do you have growing?
  • None :D

I have two plants going, one has (the pics) discoloration showing. I topped her yesterday. The other is perfectly normal, no abnormal signs. Thoughts?

 

[flossdaily]

I should add that prior to the nutrient change, they had been in a 1/4 strength solution in the buckets under high blue spectrum light. When I changed the nutrients up to full strength, I also turned on the red setting for a fuller spectrum.

The large leaf you see with yellowing, began about a week ago (under blue light heavy, and the 1/4 strength nutrient solution) - I noticed the discoloration as it was beginning to form (as you can with the two new shoots that are beginning below). What's odd is that the topping I did yesterday, none of the leaves that were growing had any discoloration.

 

[cemchris]

What ratio are you running on 3 part? Doubtful it is S depending on the ratio. If you are on RO and running micro on the lowend it could just be a micro issue. If it is only that one plant in that one spot I wouldnt go chasing a demon unless it starts to spread to other plants.

 

[flossdaily]

I'm using 1tsp CaliMagic per gallon (for additional calcium and mag), and then 2tsp micro, 3tsp grow, and 1tsp bloom.

 

[Aqua Man]

Variegated leaves... Wouldn't worry about it.

Looking over fed could be because of your low. Humidity. I would lower the ppm and increase the humidity

 

[flossdaily]

Variegated leaves... Wouldn't worry about it.

Looking over fed could be because of your low. Humidity. I would lower the ppm and increase the humidity

Suggestions on lowering PPM? Just adding fresh pH balanced ro water? Given that the other plant seems unaffected, makes sense that maybe I just wait it out

 

[Aqua Man]

Suggestions on lowering PPM? Just adding fresh pH balanced ro water? Given that the other plant seems unaffected, makes sense that maybe I just wait it out

Sure up to you. They just look a bit over fed and your humidity is low which increases nutrient uptake. The variegated leaves are of no concern.

 

[flossdaily]

Sure up to you. They just look a bit over fed and your humidity is low which increases nutrient uptake. The variegated leaves are of no concern.

I gotcha, ok. What should I be targeting for PPM, using RO water? And, is that ratio (1:2:3:1 /gal calmag:mico:grow:bloom) a good ratio (it's what the bottles say)?

 

[Aqua Man]

I gotcha, ok. What should I be targeting for PPM, using RO water? And, is that ratio (1:2:3:1 /gal calmag:mico:grow:bloom) a good ratio (it's what the bottles say)?

If your using straight RO. First add cal mag to reach 100-150ppm then add nutrients in the ratios suggested on the bottle. The ppm will differ depending on stage of growth but the ratios need to be used as suggested. Your ppm is good at 200 but you want to raise your humidity to about 60-65%.

So RO water then add 100-150ppm of cal mag. Then add 200ppm of nutes mixed in ratios as per the bottle. That puts you at 350ppm. Then ph down to 5.8.

 

[flossdaily]

If your using straight RO. First add cal mag to reach 100-150ppm then add nutrients in the ratios suggested on the bottle. The ppm will differ depending on stage of growth but the ratios need to be used as suggested. Your ppm is good at 200 but you want to raise your humidity to about 60-65%.

So RO water then add 100-150ppm of cal mag. Then add 200ppm of nutes mixed in ratios as per the bottle. That puts you at 350ppm. Then ph down to 5.8.

That's been my exact process! :) And I'm still at 200 ppm according to my meter (which may well be off). I got my Atlas Scientific sensors in a few weeks back, I'll get them set up and calibrated this weekend.

 

[Aqua Man]

That's been my exact process! :) And I'm still at 200 ppm according to my meter (which may well be off). I got my Atlas Scientific sensors in a few weeks back, I'll get them set up and calibrated this weekend.

Ratios meaning in proportion to each other. The amount may be to much. It's likely your ppm meter is a bit off. You can make a test solution if you have a scale.

 

[Aqua Man]

Here ya go. This will answer your question on your ppm meter.



Use distilled water for this

 

[Jimster]

These guys have the right information. While your plants look good, they shouldn't be showing much in the ways of nutrient deficiencies yet. Just about any growing medium, even Promix or bare coco will have enough nutrients in it to get your plants growing thru the first month... even longer if fertilizer is added. It looks like they are getting overfed, at least to me. They don't look to be in bad shape or dying, although I would cut back to the 1/4 to 1/3 range until things sort themselves out. It's a good sign that the new growth looks good, but keep an eye out for the plant getting enough nitrogen (plant gets gradually lighter in green color), since it will use a lot of nitrogen during vegging and since you are cutting overall nutrients back if following this advice.

 

[flossdaily]

Appreciate all of the insights here folks. I've diluted the overall solution quite a bit, and I'll be moving the fan (currently a single fan) out of the tent in favor of two smaller ones that are easier to control so there isn't a bunch of direct wind on the plants (which from what I understand, promotes respiration and could be compounding the overfed symptoms). It's been an additional couple days since my OP, and the plants still look mighty healthy to me -outside of the one plant having odd blotches of discoloration, the other plant has none. And where there's discoloration on the one plant, the structure of the leaf is super healthy looking to me, the surrounding leaflets are deep green, no signs of drying or other issues.

As an aside, I'm currently fighting conflicting readings between my digital pH probe vs. the liquid drops (read by color). I've calibrated my probe twice using the supplied calibration solutions and the probe reads them correctly (the expirations on the bottles are for '21). But there's about a .75pH difference (probe reads lower) between what I read by color drops vs. what the digital probe tells me. So I've got third-party calibration solutions coming as an independent test. I also checked to make sure I wasn't seeing electrical interference by scooping some of the nutrients into a beaker and testing the pH from there, and it read the same. Have any of you all noticed weird discrepancys like this before between pH reading techniques?

 

[Aqua Man]

Appreciate all of the insights here folks. I've diluted the overall solution quite a bit, and I'll be moving the fan (currently a single fan) out of the tent in favor of two smaller ones that are easier to control so there isn't a bunch of direct wind on the plants (which from what I understand, promotes respiration and could be compounding the overfed symptoms). It's been an additional couple days since my OP, and the plants still look mighty healthy to me -outside of the one plant having odd blotches of discoloration, the other plant has none. And where there's discoloration on the one plant, the structure of the leaf is super healthy looking to me, the surrounding leaflets are deep green, no signs of drying or other issues.

As an aside, I'm currently fighting conflicting readings between my digital pH probe vs. the liquid drops (read by color). I've calibrated my probe twice using the supplied calibration solutions and the probe reads them correctly (the expirations on the bottles are for '21). But there's about a .75pH difference (probe reads lower) between what I read by color drops vs. what the digital probe tells me. So I've got third-party calibration solutions coming as an independent test. I also checked to make sure I wasn't seeing electrical interference by scooping some of the nutrients into a beaker and testing the pH from there, and it read the same. Have any of you all noticed weird discrepancys like this before between pH reading techniques?

Take you ph pen to the grow store most have no issue validating it's accuracy.