brown leaf edges

"Help" can anyone help i have started with brown leaf tips on my young plants, first week in system 3 weeks old i am not sure if it is heat stress temps 25deg c or potassium def i am running flood and drain system.
I was using dutch master for the fist time a and b gold range with add .27 at 0.8 ec.
I have now gone back to vitalink max a and b at 0.8 ec to see if this will sort the problem had no problems with this before.

Running 250w cfl temps 25deg c light on
21deg c light off
humidity max 60%
min 45%

.8 ec is 400ppm should not be too high, I would try lowering th ec I believe brown tips is a sign of overfert. don't know if you have one but here's a conversion chart.

[TABLE="width: 146"]
[TR]
[TD="class: xl65, width: 131, bgcolor: transparent"][/TD]
[TD="class: xl64, width: 64, bgcolor: transparent"]Hanna[/TD]
[/TR]
[TR]
[TD="class: xl65, bgcolor: transparent"] EC [/TD]
[TD="class: xl66, bgcolor: transparent"]ppm[/TD]
[/TR]
[TR]
[TD="class: xl64, bgcolor: transparent, align: right"] 0.1 [/TD]
[TD="class: xl66, bgcolor: transparent"] 50[/TD]
[/TR]
[TR]
[TD="class: xl64, bgcolor: transparent, align: right"]0.2[/TD]
[TD="class: xl66, bgcolor: transparent"] 100[/TD]
[/TR]
[TR]
[TD="class: xl64, bgcolor: transparent, align: right"]0.3[/TD]
[TD="class: xl66, bgcolor: transparent"] 150[/TD]
[/TR]
[TR]
[TD="class: xl64, bgcolor: transparent, align: right"]0.4[/TD]
[TD="class: xl66, bgcolor: transparent"] 200[/TD]
[/TR]
[TR]
[TD="class: xl64, bgcolor: transparent, align: right"]0.5[/TD]
[TD="class: xl66, bgcolor: transparent"] 250[/TD]
[/TR]
[TR]
[TD="class: xl64, bgcolor: transparent, align: right"]0.6[/TD]
[TD="class: xl66, bgcolor: transparent"] 300[/TD]
[/TR]
[TR]
[TD="class: xl64, bgcolor: transparent, align: right"]0.7[/TD]
[TD="class: xl66, bgcolor: transparent"] 350[/TD]
[/TR]
[TR]
[TD="class: xl64, bgcolor: transparent, align: right"]0.8[/TD]
[TD="class: xl66, bgcolor: transparent"] 400[/TD]
[/TR]
[TR]
[TD="class: xl64, bgcolor: transparent, align: right"]0.9[/TD]
[TD="class: xl66, bgcolor: transparent"] 450[/TD]
[/TR]
[TR]
[TD="class: xl64, bgcolor: transparent, align: right"]1[/TD]
[TD="class: xl66, bgcolor: transparent"] 500[/TD]
[/TR]
[TR]
[TD="class: xl64, bgcolor: transparent, align: right"]1.1[/TD]
[TD="class: xl66, bgcolor: transparent"] 550[/TD]
[/TR]
[TR]
[TD="class: xl64, bgcolor: transparent, align: right"] 1.2 [/TD]
[TD="class: xl66, bgcolor: transparent"] 600[/TD]
[/TR]
[TR]
[TD="class: xl64, bgcolor: transparent, align: right"]1.3 [/TD]
[TD="class: xl66, bgcolor: transparent"] 650[/TD]
[/TR]
[TR]
[TD="class: xl64, bgcolor: transparent, align: right"]1.4[/TD]
[TD="class: xl66, bgcolor: transparent"] 700[/TD]
[/TR]
[TR]
[TD="class: xl64, bgcolor: transparent, align: right"]1.5[/TD]
[TD="class: xl66, bgcolor: transparent"] 750[/TD]
[/TR]
[TR]
[TD="class: xl64, bgcolor: transparent, align: right"]1.6[/TD]
[TD="class: xl66, bgcolor: transparent"] 800[/TD]
[/TR]
[TR]
[TD="class: xl64, bgcolor: transparent, align: right"]1.7[/TD]
[TD="class: xl66, bgcolor: transparent"] 850[/TD]
[/TR]
[TR]
[TD="class: xl64, bgcolor: transparent, align: right"]1.8[/TD]
[TD="class: xl66, bgcolor: transparent"] 900[/TD]
[/TR]
[TR]
[TD="class: xl64, bgcolor: transparent, align: right"]1.9[/TD]
[TD="class: xl66, bgcolor: transparent"] 950[/TD]
[/TR]
[TR]
[TD="class: xl64, bgcolor: transparent, align: right"]2[/TD]
[TD="class: xl66, bgcolor: transparent"] 1000[/TD]
[/TR]
[TR]
[TD="class: xl64, bgcolor: transparent, align: right"]2.1[/TD]
[TD="class: xl66, bgcolor: transparent"] 1050[/TD]
[/TR]
[TR]
[TD="class: xl64, bgcolor: transparent, align: right"]2.2[/TD]
[TD="class: xl66, bgcolor: transparent"] 1100[/TD]
[/TR]
[TR]
[TD="class: xl64, bgcolor: transparent, align: right"]2.3[/TD]
[TD="class: xl66, bgcolor: transparent"] 1150[/TD]
[/TR]
[TR]
[TD="class: xl64, bgcolor: transparent, align: right"]2.4[/TD]
[TD="class: xl66, bgcolor: transparent"] 1200[/TD]
[/TR]
[TR]
[TD="class: xl64, bgcolor: transparent, align: right"]2.5[/TD]
[TD="class: xl66, bgcolor: transparent"] 1250[/TD]
[/TR]
[TR]
[TD="class: xl64, bgcolor: transparent, align: right"]2.6[/TD]
[TD="class: xl66, bgcolor: transparent"] 1300[/TD]
[/TR]
[TR]
[TD="class: xl64, bgcolor: transparent, align: right"]2.7[/TD]
[TD="class: xl66, bgcolor: transparent"] 1350[/TD]
[/TR]
[TR]
[TD="class: xl64, bgcolor: transparent, align: right"]2.8[/TD]
[TD="class: xl66, bgcolor: transparent"] 1400[/TD]
[/TR]
[TR]
[TD="class: xl64, bgcolor: transparent, align: right"]2.9[/TD]
[TD="class: xl66, bgcolor: transparent"] 1450[/TD]
[/TR]
[TR]
[TD="class: xl64, bgcolor: transparent, align: right"]3[/TD]
[TD="class: xl66, bgcolor: transparent"] 1500[/TD]
[/TR]
[TR]
[TD="class: xl64, bgcolor: transparent, align: right"]3.1[/TD]
[TD="class: xl66, bgcolor: transparent"] 1550[/TD]
[/TR]
[TR]
[TD="class: xl64, bgcolor: transparent, align: right"]3.2[/TD]
[TD="class: xl66, bgcolor: transparent"] 1600[/TD]
[/TR]
[/TABLE]

"update" now i using vatalink max everything is starting to look good again i think the dutch master must have something a little strong in it for small plants even if the ec is at the recommended level.
Its a funny old game ha ha