New Grower Can someone help me fix this?

[Exusiaa]

This started last week a little & since then the leaves are getting worse. Theyre crisping from the centre tip down the leaves , plants are 25 days old , just seems to be the bottom leaves at the moment but looks like it might work up the plants , im using a 400w hps about 3 ft away from plants , any advice & help would be much appreciated thanks. & cant seem to upload all the pics :s

 

[Exusiaa]

Cant drag and drop the better pics to attach them on my phone :/

 

[derek420colorado]

I can see your pictures and from what I can tell it looks like you may have given them a little bit of nute burn, but I am not 100% sure. I would post this in the Infirmary for sick plants or the AFN live 24 hour help line, it will get the most eyeballs on your problem and the folks in those two forums are amazing at helping diagnose problems. You said it looked like it was spreading, that is why I am not 100% because if it was just on that one leaf then I would say defintly nute burn early on. What is your feeding schedule at the moment? Do you use PPM or EC to measure your nute strength. Also what is your pH and your temps inside your grow space, these are all important factors when trying to determine what is wrong with your ladies. Hope this helps and I am sending super healthy grow Karma your way friend