Bob,
I've got 80 watts of light. The water is quite hard - actually in most of
the UK what comes out of the tap is liquid cement. Does this cause a huge
problem ? The plants seem to be growing fine.The elodea and the cabomba grow
rapidly but then come off the bottom. The elodea has plenty of roots
springing from the stem.
Are these plants not supposed to be pushed into the sand ?
Cheers,
Prakash.

"Bob Alston" wrote in message
...
I would wonder if you have enough light. As I recall, fine leaved plants
need relatively high light. I would suggest somewhere in the range of 2-3
watts per gallon. If you have just the standard light that came with the
tank, you probably have too little light.

Also, your water seems pretty hard for doing CO2.

Bob
"Prakash" wrote in message
...
Hi,
I've got a 42 UK gallon tank, sand substrate, DIY CO2 and a number of
plants. ph is 7.6, GH and KH hover around 12 degrees. I'm new to this,
and
have had the tank for about 12 weeks. Initially I had a lot of plants
(dont
know all their names yet), and they all seem to be growing well. However
I
have had increasing trouble with the fine leaved plants such as elodea,
cabomba etc. All of them seen to rot at the base and then just float up
and
swirl around in the circulation. The leaves etc seem fine, its just the
base
that rots.

Any suggestions on how I can stop this ?

TIA,
Prakash.