[jeffrey richard]

Any advice or should they be treated as any submersed crypt (wendtii ?)?

 

[HeyPK]

Pretty much as any submersed crypt. They get big and can cover over and shade out smaller crypts. Picture below shows some C. cordata (closely related to blassii) just getting started and on the way to growing over C. undulata.

Edit: (Picture placed on Pbase, so you should be able to see it now.)

 

[rs79]

Picture? I don't see no steenking picture...

 

[HeyPK]

Picture? I don't see no steenking picture...

They just moved the plant pictures to another server, and all the links to the pictures don't work any more.