What's Wrong With My Betta :(

[Gtilar]

Not sure if it is fin rot, checked the water quality and all is good (ammonia:0 nitrate:20 nitrite:0) Been like this for more than 4 weeks. It does not look like there is any changes regarding to fin rot as my betta seems to flare and also his fins seem to not show any difference in rot. Have silk plants and an ornament (which he hangs around in) those two do not seem to cause any harm on his fins either. Not sure what I should do. Either wait and see longer or find some other solutions from you guys
 
Below are the pictures of my Betta I took today: 
 
http/s1360.photobucket.com/user/Gnoz_Wayne/media/20130704_233918_zpsb23dfd21.jpg.html
 
http/s1360.photobucket.com/user/Gnoz_Wayne/media/20130704_233958_zps73f33cec.jpg.html

 

[Blondielovesfish]

I personally don't think it's fin rot (I may be wrong though), I think it may just be his markings.

 

[SamB]

I am not seeing the damage you are referring to. Do you have a before picture? Might want to lower that nitrate. What is the ornament? 

 

[KasumiBetta]

It looks like he's got a little red wash (or some darker pigment) running through his fins, but I don't see anything beyond normal color.

 

[Mamashack]

I think the dorsal fin looks a bit ragged at the edges in the 2nd picture. Watch him closely as someone recently reported their betta's fins had been caught in the filter and she only noticed what was causing it after a few days of thinking he might possibly be self-harming. Keep the water clean, fresh and warm and any wounds should heal. How often do you do water changes, Gtilar? Weekly is beneficial to replace minerals and electrolytes. Tho you might consider twice weekly whilst he's recovering.
 
Try Indian Almond Leaves if you can get some as they are soothing in all respects. They make the water look a bit brown but I don't mind that and they are very effective. Your profile doesn't state where in the world you are but I know they are readily available in the UK from Ebay.
 
Don't worry about that nitrAte level - try to run it at no more than 20ppm over the replacement water nitrAte level. My tap water runs at 10-20ppm so 40ppm is acceptable in mine.

 

[Wildbetta]

His tail looks good to me.  I see no evidence of fin rot at all.  His tail has a red wash which makes it have that color.  His dorsal fin does look a bit ragged in the second pic but that could just be from the way the pic was.  Keep the water warm and very clean and you should have no issues.