Crypts and Light

It's not specifically the INCREASE in light that caused the crypts to
melt--it's simply a significant change in lighting that did it.  They require
a stable environment--stable water chemistry, temperature, and light
level...when any of these varaibles are changed significantly, cryptocorynes
go into their "melt and regrowth" phase.  Just leave the additional light on
the tank...it'll be good for the cyptocorynes in the long run--but they'll
have to regrow from scratch again.