Tip browning problem

[thbjr]

My Sarrs and Cephs have a leaf tip browning problem. Conditions are 50%-70% humidity, 75-85 degrees, 50/50 peat perlite, RO @ 5ppm, plenty of air circulation. Here are the pics. Also note the center rib of the Cephs pitchers as well as the tios of the non-carnivorous leaves. :-(
Suggestions?

 

[theyellowdart]

Are they all recieving light from the same source?

 

[JB_OrchidGuy]

My plants outside in full sun do this and sometimes even before the pitchers even open. I am not sure what causes it. What kind of water do you use? I knwo with orchids you can get leaf tip burn by fertilizing too much. I am thinking it might be because of my water. So just curious as to what you use.

 

[thbjr]

Are they all recieving light from the same source?

Yep, 4, 4' 6500K fluorescsent tubes.

My plants outside in full sun do this and sometimes even before the pitchers even open. I am not sure what causes it. What kind of water do you use? I knwo with orchids you can get leaf tip burn by fertilizing too much. I am thinking it might be because of my water. So just curious as to what you use.

RO that my TDS tester shows at 5 PPM. It really does remind me of fert burn, but they've never been fertilized (and I'm not using Miracle Grow peat or perlite. Bulk bags of each from Home Depot). Shoot, I haven't even feed them insects.

 

[xvart]

Possibly not enough light?

xvart.

 

[thbjr]

Here is my peat and perlite.

 

[xvart]

Gotta love those peat bales. Looks familiar...

xvart.