i got this plug of U. nephrophylla almost a year ago from Tamlin. i thought i had killed it but i left the pot alone and about 6 months ago i saw some new growth. a couple months ago i repotted it from a peat mix into a layer of LFS over top a layer of perlite and orchid bark going by info that Pyro gave me and now look what i got along with a growth spurt:
here is a pic of U. calycifida 'Yog-sothoth'
and here is a wierd double leaf on my U. nelumbifolia