Your e-mail address says Duke so I'm a neighbor over in the RTP.
Drosera problems, some thoughts:
We've been having some pretty fierce heat this summer. You may want
to cut back on the early PM sun for a while and maybe raise the
water level a bit.
Could you be having a buildup of minerals in your water trays? You
might try flushing out the pots (fresh water from the top) and frequent
water changes in the trays. If the water is chlorinated, does it
stand a bit before use?
Try fertilizing your plants with a 1/8 strength miracid solution.
Either water the soil or spray on the leaves (this will trigger
leaf movement also). Don't let the plant flower unless you really
want the seeds since it draws a lot of strength from the plant.
Take care!
Jeff
welch@niehs.nih.gov