New Grower Problems feeding in COCO please help.

[514Grows]

Problem: Lime green new growth, very slow growth, plant barely drinking.

Medium/grow method: Coco with autopots (bottom feed system)

Feed: and supplements used: Megacrop and cal mag

water source: 100ppm tap

Strain/age: SpaceWalker archive seedbank (photo I know)

light used: 240W 3500k Quantum board

Climate: 21-25 C 45-55% RH

Additional info:
New shoots arent growing much as well and the tips on the new growth are burnt? Not sure if this is due to lockout from autopots but it kinda looks like burn from too much PK or a sulfur deficiency? Manganese or Iron deficiency? Im feeding at the recommended 1390 EC my base water is 200 EC so 1590

Could I be mixing my nutes wrong? I add 4ml/gal calimagic and which gives me about 600-700 EC and then I add mega crop until I get too ~1.5 EC, When I add the recommended amount of grams to my mix after I cal Mag I end up with a solution around 2 EC which is way too high? Am I supposed to cut the cal mag and use only mega crop? I have sweet candy as well but I haven't used it yet. I top flushed a few times so maybe I flushed down the salt buildup from the top of the coco into the root zone but I highly doubt that cause my runoff was 1300EC and I ran 5 gallons through it. Im using Hydroguard as well so it cant be root rot.

someone please help I have no idea what to do to correct this, I had one or two fungus gnats so I dusted the top of the coco with diatomaceous earth and i got a bunch of yellow traps which havent caught anything in a week so i doubt the problem is bugs.

 

[514Grows]

Waiting on my blue lab pen will return with runoff Ph and EC soon

 

[Proph]

Hello! Sorry you're having issues, but every issue is a learning opportunity!

Couple of questions.. Why are you using so much calmag? Did you have a calcium or magnesium issue early on or something? I don't use mega crop, but it has calcium in it doesn't it? How did you flush the plants? You memtioned salt build up.. Are you using a salt based nutrient? From what I know mega crop is not salt based.. So just curious as to where the salt build up would be coming from.. What is the ec after the flush?

Honestly, the plants just look a little stressed and maybe even hungry again, depending on where the ec ended after the flush that was done.

 

[514Grows]

EC after flush was 1400 but i flushed it with nutes at 1540 EC. ur right it cant be salts. hard to test root ph with coco but the runoff was at 6.6 and in my autopot tray its at 6.4 maybe a bit high. Ill make sure to keep my res at 5.9 now that i have my blue lab pen! I flushed it over a bucket. Ill lower the cal mag too.

 

[St. Tom]

i dont use megacrop i use remo with autopots i would start adding your megacrop to your food first and add your calmag last to get to the correct ec your after in late veg i only got up to 1.6 max and in flower most strains i never go over 1.8 i would lower your ec slightly with your feed and let them get on as normal .remember most things take days or even a week to get back on track so expect them to look different overnight also by going by your pics they look fine to me so try to stop stressing growbro

 

[St. Tom]

also one more thing try lower you ph in your res to say 6.0 and that will be around the sweet spot also i always feel underfed is better than overfed

 

[Proph]

EC after flush was 1400 but i flushed it with nutes at 1540 EC. ur right it cant be salts. hard to test root ph with coco but the runoff was at 6.6 and in my autopot tray its at 6.4 maybe a bit high. Ill make sure to keep my res at 5.9 now that i have my blue lab pen! I flushed it over a bucket. Ill lower the cal mag too.

Flushes aren't some using nutrients. Flushes are done with zero ppm RO water. The purpose of flushing is to rid the soil/medium of excess salt or nutrient build up.. You aren't getting rid of anything by using water that is 1500 ppms. The objective of the flush is to lower the run off ppms. It's really tough to pinpoint the exact issue at this point. There could be a nutrient lock out of some sort happening caused by feeds that high, but it's hard to say. I'd feed at normal strength and lay off the Cal mag until it's needed

 

[514Grows]

Flushes aren't some using nutrients. Flushes are done with zero ppm RO water. The purpose of flushing is to rid the soil/medium of excess salt or nutrient build up.. You aren't getting rid of anything by using water that is 1500 ppms. The objective of the flush is to lower the run off ppms. It's really tough to pinpoint the exact issue at this point. There could be a nutrient lock out of some sort happening caused by feeds that high, but it's hard to say. I'd feed at normal strength and lay off the Cal mag until it's needed

I think I got rid of hotspots and equalized the ph throughout the medium, they are much healthier now already. My ph was way off because of a cheap pen. Isnt it bad to water coco without anything at all? Fucks up the CEC?

 

[Proph]

I think I got rid of hotspots and equalized the ph throughout the medium, they are much healthier now already. My ph was way off because of a cheap pen. Isnt it bad to water coco without anything at all? Fucks up the CEC?

No, it's not bad to water coco with plain water.. Especially when talking about flushing.. But that's something you'll probably learn on your own in time. Im glad they have perked up for ya. Give an a few days to recover and let us know how it's going!