I have never had success growing Cobras in a terrarium. They need their
roots to stay cool & wet at all times and they almost always want the
water moving (like a stream). They need to be well-drained and very wet
at the same time ... complicated, but well worth it when you get the
right combo.
Sounds like the brown cobra is gone. I would get it out befor the "white
stuff" (which sounds like a dreaded fungus) spreads to the other plants.
I would strongly advise potting each of your plants up individually and
then placing them in the terrarium -- maybe using a little of the dead
sphagnum for "looks." (But be careful with this stuff, too -- it can
breed fungus & pests.)
IT doesn't sound like there is enough light to me. Most CP (not all!)
really enjoy the light. Without it you won't get the growth you want.I
grow all of my CP outside now, under 70% shade cloth (there is still
quite a bit of light) and the plants are loving it.
I would suggest adding a little perlite to your medium. Even with the
sand added (good for the acidity) it can be a lttle heavy for some of
the plants (the cobras NEED much better drainage).
I hope these suggestions help. =
Happy Growing!
Ken Cusson
-- =
+---------------------------------------+
+^^^^^Get revenge on that mosquito =85^^^^+
+^^^^^^^^Grow a Venus Fly-Trap!^^^^^^^^^+
+^^^Ken Cusson (ccskenc@redshift.com^^^^+
+^^^^^^^^^^or ken@casadyg.com)^^^^^^^^^^+
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