Re:Crypt rot

> I have a bunch of Cryptocoryne sp. (probably wendtii or lutea) in my 45
> gallon heavily planted aquaria (see, for instance,
> http://marge.phys.washington.edu/fish/Plants/People/Olson/ for full
> desctiption).  The tank has heating cables, CO2, and 160 watts of fluorescent
> lighting.  Starting about 2-3 weeks ago, virtually ALL of the brown "wendtii"
> began to melt; I went on vacation and now that I'm back it's completely gone
> except for a few newer shoots.  More of the green "lutea" seems to have
> survived, planted in the same area & mixed with the brown "wendii".

Sorry about the meltdown.

> So... I would like to learn more about Crypt rot.  Is this a seasonal
> thing, perhaps triggered by changes in our water?  Is it a reaction to
> other plants?  Given my situation, I don't think it's due to a change in
> macronutrient level (which most of the books suggest) as that's been pretty
> constant.  I have noticed in the past that SOME of the crop will die out
> and come back, but I've never had such a mass suicide as this.

Having read your articles in the Krib, I am pretty sure you've read
the description of crypt rot that they mention in the Dupla book.

When I read it, I was surprised that they seemed to describe it 
as a different malady than crypt meltdowns (maybe I just didn't
read the book carefully enough).

They seemed to think crypt rot is caused by sustained high iron

I have found that my crypts stopped melting regularly after I
began CO2 injection and increased my lighting.  I found that they
would melt if I broke the leaves or bent them over too much while 
cleaning algae off.  Before I added CO2 and more light, I had to
remove red algae on a weekly basis.  I no longer need to do this, 
and my crypts still have the leaves that they had when I made 
the change (along with a few newer, longer, more colorful leaves).

The meltdowns occurred after cleaning the leaves.  At first, I just
scrubbed the algae off with my fingers.  This was very hard on the
plants and tended to un-settle them a bit.  If I unsettled one,
it would melt.  If I accidentally pulled the end off of a leaf,
the leaf would melt.  

Shortly before adding light and CO2, I switched to a toothbrush
for cleaning the leaves.  This really helped.  If I damaged a
leaf, the damaged part would start to rot, but the leaf would'nt
melt down.  Now I don't need to clean the leaves myself.  My 
ottocinclus handle that part for me.

I also had one near fatality (the jury is still out) with a crypt
(I think it's wendtii) whose longest root became uncovered.  The
root melted, then the leaves melted.  The plant poked up a tiny 
leaf a few weeks ago, but I haven't seen any additional growth
since then.

I'm wondering if your tank had a temperature or pH fluctuation
while you were gone that caused your crypts to "go deciduous"
on you.

BTW, I was reading in your setup description about your Nymphaea.
Have you had any more success with them?  I purchased two african
water lillies (red) a few weeks ago and they haven't done a lot
yet.  My aponogeton crispus, on the other hand, are flowering.

Hope your plants come back,

David W. Webb      
dwebb at ti_com

Any correlation between my opinions and those of Texas 
Instruments is purely coincidental.  (I don't speak for