24/0 Veg not working? Plant prone to issues. Why?

Hi guys,

I'm starting out my first grow with Dr Seed's Do-Si-Dos in DWC and been using 24/0 light for veg since sprout, currently on Day 25.

Nutrients
Ludicrous Nutrients (all-in-one type, with 2.5% cal, 1.5% mag)
Had to supplement Calmend (CalMag with 3.2% cal, 1.2% mag)
140 ppm tap water

Light
170W LED actual wattage - Distance from plant is 18"

Issues
Stunted growth. Slow growth. The plant has been showing calcium & magnesium deficiencies since sprout. I had to supplement with 30ppm Calmend. After recovering with green foilage on the 2nd node, 3rd node is back showing deficiencies. This time instead of just adding Cal/mag, I increased nutes from 450 to 550 ppm. After this I experience nute lockout and PPM rising the next day. I lowered PPM via dumping half the rez and filling with 140 ppm tap water + 60 ppm cal/mag (200 ppm total). New rez is 400 ppm. From here onwards, I keep seeing the PPM's rise daily and I'm now on the 4th day constantly lowering the PPM back to around 400. I notice the rising PPM's have slowed down daily though and went from 150 ppm increase to 60 ppm to 40 ppm and now currently ppm has not moved today yet.

During this entire time of battling rising PPM's, my lower node leaves have reddened stems, interveinal yellowing then whitening then drying up and curling. This interveinal yellowing and whitening, is very obvious to notice it's the worst damage right under the LED light. Although, this has progressed all over the plant over the last week.

Root health is healthy as can be. Cream-coloured and white and very expansive, much much larger than leaf growth, it's weird to me when I see other people's pictures of their leaf vs roots at the same Day stage.

Question
I seem to be experiencing so many issues as if the plant is so sensitive and the fact my above root growth is so slow. With the kinds of damage related to photosynthesis I saw, I suspected it had something to do with my light setup or schedule. I thought maybe it's too much light? First, I thought my all-in-one nutrients would have enough Cal/Mag with its ratios but I had to add more with Calmend. That led me to believe something is wrong with my light setup needing more Calmag. Calcium and Magnesium are crucial in photosynthesis. I've also thought maybe my 170W LED 18" away is too close.

Is 24/0 schedule a more stressful schedule more prone to problems? Can someone tell me if this is true based on your growers' experience, not just hearsay? Or is it 550 PAR is too much for veg? Help please. Should I switch to 18/6 veg? Have you guys experience less problems with 18/6 vs 24/0?

some strains dont respond well to 24 hour lighting . Some can handle but for others its too much stress on the plant as its going to be sleeping for a few hours anyway regardless if the lights are always on . Try switching to 18/6 or at least 4 hours off and you will see better results

I much prefer an 18/6 veg cycle. With intense lighting the plants look pretty tired after 17 hours, by 18 they are ready for a nap and perk back up within an hour after lights out.

Plants don't stop growing when the lights are off. They use carbohydrates metabolized during photosynthesis to grow. You will notice fresh light growth on the tops when the lights come on, that quickly darkens with exposure to light.

Also your PPM is really low. I would get up around 900 - 1000 PPM and feed them.

Yeah, so my plants are doing a lot better now. I noticed all the damage only on the top canopy so I suspected it's the light or something. I went to 20/4 light schedule for a week which was wayyyyy better. I upped the nutes to 600+ and got Potassium Silicate and it seriously helped uptake because now I see ppm's constantly drop 50-100ppm everyday since.

I went 18/6 for 2 days then defoliated a bit and flipped to flower 12/12 next day.

This is Day 35. She's been FIM'd, defoliated, and LST'd. She looks way, way better. Way bigger stems and massive roots now. I'm at 1000ppm now and it keeps dropping to 840ppm the next day. Should I keep topping it back to 1000ppm or let it drop?

pr3tti said:

Should I keep topping it back to 1000ppm or let it drop?

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Top it back or risk deficiencies.

How often do you change out the nutrients? If you do too many add backs the balances of the elements can get out of whack.

Renfro said:

I much prefer an 18/6 veg cycle. With intense lighting the plants look pretty tired after 17 hours, by 18 they are ready for a nap and perk back up within an hour after lights out.

Plants don't stop growing when the lights are off. They use carbohydrates metabolized during photosynthesis to grow. You will notice fresh light growth on the tops when the lights come on, that quickly darkens with exposure to light.

Also your PPM is really low. I would get up around 900 - 1000 PPM and feed them.

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Agreed.
After 15hrs or so, you can tell they're "tired".
As far as reliving stress for them, let your nose be the judge 5 minutes after the lights go out.

They definitely benefit from their "sleep".

Renfro said:

Top it back or risk deficiencies.

How often do you change out the nutrients? If you do too many add backs the balances of the elements can get out of whack.

Click to expand...

I do a rez change once every 2 weeks. I try not to change rez until i have to

pr3tti said:

I do a rez change once every 2 weeks. I try not to change rez until i have to

Click to expand...

Well I suggest you do it more frequently during flower, especially days 20 - 50 of 12/12 when they are at peak consumption.

I'm just done Week 1 flower now. And my FIM'd work'ed perfectly! I managed to get 10 main tops, 8 surrounding and 2 inside. Weee! This is my first grow so as you can tell I'm quite excited

EDIT: @Renfro i followed your advice on topping her up everytime ppm falls and she's doing wonderfully

Your problems have nothing to do with light schedule, and everything to do with PH and ppm issues. U can run 24 - 0 with out any problems