Hey growmies, im not sure whats going on.
Im runnin full cyco nutes line( have done for 3 grows and no issues)
In coco 70%30 perlite indoors under mars hydro fce 8000. At about 550ppfd for mid/late veg. I notices bright yellow nodes about a week ago but im growing dos si dos fem sweds from weedseedexpress. From phots off google dosi does have yellow nodes but now as you can see something else is going on… ive been light on watering so i thought maybe a salt build up causing iron lock out. So i flushed till runoff and for 2 days now have watered/fed till runoff so that there is no salt build up… im unsure if its gotten better or worse in those 2 days… like it looks greener in some spots but browning more in otheres. Experience is needed… all help is appreciated guys dont be shy 
Sounds to me as if your “light watering” may be part of the issue here. When growing in Coco you should always feed until there is some run off or as you know, the salts will build up in the medium ( never allow coco to dry out ) I am not familiar with the nutrient line you are running, but when doing a “flush” to expel built up salts, don’t use just plain water. Rather lower the EC by around 25% or so and then set PH and do a flush in the dark cycle about 3 hours after lights out in flower ( I typically run my EC at 1.8 then flush at 1.4 )
Plants don’t like being shocked by being “starved”
Hope this helps, but I’m sure more experienced growers on here will chime in and steer you in the right direction on this one…
Yeh lesson learnt man. Hope ill see some improvements. And my nutes line has a flush/klense product that i used and p/h set too 5.7. but appreciated for the reply👍
What was the run off PH and PPMs? These 2 will tell you what’s going on in the medium 
Water to 10-20% runoff at least once a day. To get the benefits of growing in coco you have to keep it wet. Next time you water let it drip for a bit then collect a cup of the runoff and check the numbers @OGIncognito asked about.
Yep ok fellas will do this afternoon. Water goes in at 5.6-5.8 everytime i make sure with blue lab pen. And right now gets between 1250 and 1400 ppm which is about 1.2 e.c i think which also is measure on blue lab pen. Cheers guys will let use no what the go is this arvo
So fellas p.h went in at 5.8 and came out about 6.4 so not terrible and i think there looking abit better. Im gonna water/feed again tomorrow and check runoff and if its less than 6.4 ill no im on the right track and hopefully the girls wont take long too bounce back
Iron deficiency.
Question about your nutrients. Are you also using a product that provides micronutrients (iron, boron, manganese,…)? A lighter color of green is normal among new growth, but when it starts progressing outward it is an iron deficiency.
What I was thinking as well @Stainer101 and rare to see these days?? Thought light bleaching but noticed the fans look good. 6.4 on the run off for coco is no bueno. I suggest next feeding to go with liberal run off at 5.8 and shoot for 5.8-6.0 PPMs are high and 900-1000 works best for my coco grows
Thanks dude and ill check the nutes today too see whats in it. But like i said ive done 3 grows with cyco and never had this issue. All i did different too save money was less amount of watering were i had no runoff. So i watered 1.5 litres in a 15 litre pot when really should have been 3 litres per day too achieve good runoff. With all the chats from every and urself im almost certain its a salt build up cause its not just bright yellow nodes i think you can see some magnesium deficiency as well. And coupled with me not watering until runoff pretty much ever since seedlings im hoping thats it. Ill see this arvo and hopefully they look a little better again. Also for the americans i believe 1litre is the same as 1 US quart so same same i believe. Or 1 litre is 0.264 gallons