bit of help please

[Fluffy bud]

Hi I've had some cuttings given which was fine when i got them. Im using coco coir from the blocks you can get. They've been planted for a week but they've started going light yellow and what looks like brown spots on the ends of the leaves. I've fed them canna coco a+b but under the recommended dose. You can see by the pictures the leaves are curling under. I have some seedlings too that are going yellow but they haven't had food just ph'd water 6.0
Im a soil+water farm grower so haven't a clue what it is.

[Bethmeg]

What lights are you using? Whats the temps? Whats the humidity.?
What ec are you feeding? Whats the ec of your water? Whats the ph?
How often are you watering? How much are you giving them.

If you can answer these questions folks will have a better idea whats going on

[Chew]

I'm only a novice mate so wait for a pro to come in but, did you flush the coco through when new? Also, what EC are you feeding? Looks like nitrogen claw possibly. But like I say, I maybe barking up the wrong tree mate. A pro will come along soon...

[Fluffy bud]

Hi mate its a 600w light
Temps are 23c on and 16c off
Humidity 44 on and 68 off
Ec I don't know.
Ph is 6.0 but jist checked bucket and its jumped to 6.8 but waste is 6.5
Im watering when there dry and giving them about 500m-700m.
There cuttings so do I give them week 1-2 feed feeds or stronger first time with cuttings I've alway done from seed. Cheers

[Fluffy bud]

And I did do a wash of the coco but might of not done it good enough��

[Bud Lightyear]

Your Ph should be 5.6 to 5.8 going in and you need to know the Ec of the feed. The Ec you feed is determined by the background Ec of your source water. without these numbers your just guessing. coco blocks need a proper good clean not just a quick flush through. have you got any better pics without the HPS on ?

Regards BL

[Fluffy bud]

Theres what look like salt grains in the coco so how would I get it out? Could this be the problem and could this be why they are

[hoffmans2k]

i would use coco coir pro and not the blocks mate and the look like new clones so i would say they been put in a too big a pot for them and did you use a probagater ?

[Fluffy bud]

These are the pictures. And I got them like that. What happens if you put them in too big pots

[The Aspie Toker]

It's a little hard to tell with those lights on them. You say the tips are brown - and I can see clawing. By the sound of it, it's nute burn, and a nute be locking out other nutes, hence the yellowing.