Brown leaf tips after setup change (w/ pics)

[amsterhamster]

So, if you view my thread:

https://www.rollitup.org/grow-room-design-setup/164880-closet-cfl-first-time-grower.html

You will see I updated from 5 6500k cfls to 8 6500k cfls and 2 2700k cfls (these are all 26w).

I have been watering with superthrive (diluted to recommended daily usage) since I planted the ungerminated seeds. I have only fert'd once (4 days ago) with MiracleGro 12-4-8 fert. I was told to fert when leaves got big enough haha

Now, overnight from this, two of my plants have changed for the worse, see pics.

First image (bottom left plant):
Tips are barely beginning to turn a little yellow.

Second image (top right plant):
Tip of one leaf is brown and curling downward. Brown tip appears dry.

 

[mannurse801]

Nute burn, don't feed.

 

[amsterhamster]

Do I need to flush? or just let it ride out? Should i keep watering it, just with plain distilled?

 

[mannurse801]

A flush on those young plants will be hard on them... What soil you using? If it contains any nutes, they are time released... watering will release them, so flushing could be an issue.. Hang in there for advice on the flushing.

 

[amsterhamster]

These babies came from top soil (no nutes/ferts). They're now transplanted in my homemade soil (4part topsoil, 1part perlite, 1part sphagnum peat moss).

Top Soil
NPK 0-0-0

Perlite
NPK 0.04-0.01-0.06

Sphagnum Peat Moss
NPK 0.05-0.02-0.04

Fert (applied to soil 5 days ago, 1 day before transplant)
NPK 12-4-8

 

[ProPlayer420]

I don't start my nutes on seedlings until they are well established. most soils have enough nuitrients for them for the first few weeks. I do use one drop of superthrive in a gallon of water from start to finish in veggitive growth. And I do mean just a DROP!

 

[amsterhamster]

I don't start my nutes on seedlings until they are well established. most soils have enough nuitrients for them for the first few weeks. I do use one drop of superthrive in a gallon of water from start to finish in veggitive growth. And I do mean just a DROP!

Yep, I use two drops a gallon when planting the seed since I didn't germinate with a napkin. I use one drop now.