Yes they so melt aways...also if there arent enough nutrients they are one of the worst...they just turn brown and jellyish 
2x here,It thrives just with light no fertz or anything it just floats in my discus tank,in my shrimp tank I forgot to turn the lighton for 2 days no changes in color what so ever.It wouldn't be the temperature. I have kept them in 84 to 86 degree discus tanks with no issues