Deficiency? Excess? pH? First time growing in coco and I'm finding it harder than soil

[modshot]

Argh! I’ve changed so many things at once and now I’m kicking myself…

First the changes, then the issues…

Got a new lighting setup from Pacific Light Concepts. This is the only change I’m feeling good about. I built an 8 strip array and I love it!

I’m growing two, new to me strains - Big Bud & Gold Leaf from ILGM.

The last change is the one I’m most uncomfortable with… Growing in Coco in stead of ProMix.

I buffered the Coco in CalMag per “M.J. Coco” and have been following his feed chart/pH/PPM recommendations. As you can see I’m have nutrient issues. I’m thinking it’s either Magnesium or Nitrogen. The leaves are all pale with dark veining. Yesterday I returned to the nutrient schedule (GenHydro recommended chart) I used in soil. I set it up to 620 (PPM)/1270 (EC)/5.7 (pH). Checked about an hour after watering and the girls were looking a much healthier green. I read the run-off at 550 (PPM) with a pH of 6.8. I assumed the pH change was because of the Coco holding on to the nutrients, but was surprised at the how high of a jump it was. I haven’t read my run-off in the past.

So I’m now confused about what to do next. I figured the new light would make for hungry plants, but I didn’t think they would be starving…

So I’m hoping these pic are enough for figuring out if they need more Mg or N.

[dankbudz]

To me looks like nitro def and a bit of over watering? Leaves look really fat…

[modshot]

hmm… hadn’t thought about over watering. I’m watering/feeding at about 1500mL about every 3 to 4 days. The inter-nodal spacing is insane, super tight. And that’s at about half power on the light.

I’m going to up the N next water/feed and see where I head from there. Only three weeks in from the sprouting, so I’ve got time before the flip.

[dan10]

I assume your light is a LED(full spectrum) and coco with this combination you should add CalMag to your nutrient and make sure the intensity of your light is not too hjgh(400-600 ppfd) for veg.

[modshot]

Thanks! I’ll check the PPFD. I already have Cal/Mag in the mix and I buffered the coco with it before starting. I know you can increase the Mg with Epsom salts, but I haven’t found how the suspend it at what strength before adding it to the water/feed.

This light is really bright at half power and it’s over two feet above the tops of the plants. If I have to turn it down now, I can’t wait to see how it does during flower.

[katmwall]

I don’t have enough experience to answer your question but I have these charts! Hope they help!!

[dan10]

I grow in Promix/Perlite similar to Coco, I use CalMag every feeding until Flushing with no issues, I also got a new light(MarsHydro TSw2000) a while back to replace Burble light my plants were similar to yours maybe a bit smaller, new light was 24" above canopy at full intensity, I bleach my plants too much light around 900 ppfd , but the good news my new light is stronger, the only change to my grow was my light.

[modshot]

These are a great reference! Thanks for sending them along!

[modshot]

All the grows I’ve done until now have been in ProMix. And, honestly, I wish I hadn’t changed that aspect of my grow routine. Too many changes to workout. I stopped growing for the summer because of the humidity. Now I’m feeling a little rusty. I might go back to ProMix after this run.