68° isn't cold enough to harm your plants although it may slow their growth
somewhat. The ludwigia in particular should continue to grow satisfactorily
at that temperature. I keep my tanks at about 72° (or even a little less)
because I find it does inhibit the algae. My angels would prefer warmer
water but, then, they bitch about everything, the little *******s. In
general, your plants will grow at temperatures lower than your fish will
tolerate - in other words, you're fish will be visibly distressed before
your plants stop growing. It might nudge your lily into a dormant stage,
though.


Martin A. Gross wrote in message
m...
Group,

Four days ago, I started losing my Mint Bacopa, Sunset Hygrophila,
Wisteria, and Red Ludwigia. Two days ago, I discovered that my heater was
no longer working. The water temperature was only 68F. I, of course,
immediately bought a new heater. Considering the timing, this is
certainly
a plausible cause I would think. However, I do not see improvements in
the
remaining Sunset Hygrophila (Again, this is day two). Their new leaves
are
small and very pale - completely unlike the large, wavy, bright pink
leaves
that I have come to know. Also, I have a Dwarf Lilly in the aquarium
which
was not affected. Since it is a rooted plant, I was curious to know if it
was getting a mineral from the substrate that was not available to the
stem
plants. However, like I said, this was sudden, not over a period of time
as
I would expect to see if it were a mineral deficiency. Just incase, I
upped
my dosage of Seachem Flourish, but the only improvement I saw was in the
green algae on my driftwood.
So what does everyone think? Is the failed heater truly to blame, or
did something else, coincidentally, go wrong at the same time? If it was
the heater, will the remaining plants start producing leaves normally
again,
or should I replace them?
For current water parameters, lighting, filtration, and pictures of
the
aquarium from a week ago, visit my website at
http://marting83.tripod.com/aquarium.htm

In advance, thanks for your help,
Martin