Plant leaves turning brown?

[Morley24]

HI guys,
Just noticed my leaves turning brown on one of my plants as you can see in the pic. Any ideas what's causing this?
It's been growing rapidly for the last couple of weeks but all of a sudden I see this
I don't use CO2, have a gravel substrate and using a Fluval Aquasky LED light.
The tank is around 50gal if that makes any difference
Thanks for the help in advance

 

[bizaliz3]

I don't see a pic, can you try adding it again?

 

[Morley24]

Sorry after all that I forgot to add the picture I've added it now

 

[bizaliz3]

Have you tried rubbing the brown off with your fingers to make sure it isn't just algae? When I first started keeping live plants I had that concern until I realized it was just algae that could be wiped away! I can't really tell from the photo, sorry!

 

[Morley24]

I have tried wiping it away, a certain amount will kind of flake off but not all of it, I guess if my Pleco takes an interest in it then it's just algae. I'll keep an eye out and see what develops