Holed leaves

[Paller Endre <endre.paller at freemail_hu>]

Hi Aquatic Plant People,

I have a 220 liter (58 gal) well planted aquarium ( 
http://edak.rtlmail.hu/ideig/aki.jpg ) with sagittarias, 
vals, crypts and I have the guilty ones, the Hygrophila 
polyspermas. Guilty, because they have brown-bordered holes 
on the leaves despite the daily fertilizing, DIY CO2, and 
120W fluorescent light (although the plant grows very fast, 
and the new leaves are large and green). 
You can see a photo of the old, sick leaves here: 
http://edak.rtlmail.hu/ideig/nd.jpg . My NO3 level is 10-15 
mg/l, the Fe is about 0,5 mg/l (Sera tests). My fertilizer 
contains every nutrients (nitrate, potassium, magnesium, 
iron, zinc, molybden, bromine..) except phosphate, but I am 
told that the fish-vaste and feed can supply it. So, would 
You please tell me - considering the symptoms on the photo -
which can be the missing nutrient for my holed plants! 

Best regards,

ENDre