Plants Going Brown

[andyg81]

I added these about 5 weeks ago and the tips are going brown any ideas?

Also how to I prune them? Just cut the brown away ?

 

[N0body Of The Goat]

What lighting have you got?

What lighting period are the plants getting daily?

What is your carbon and ferts regime?

 

[andyg81]

No co2
There was a fert tablet put under each one when I put them in.
And lights on about 6 hours a day
Water stats Amonia 0 nitrites 0 nitrates 20

Lighting is the standard ones that come with a juwel 180

 

[andyg81]

Do I just cut the brown off or all the way to the bottom of the stem ?