Subject: Photosynthesis?

> I recently received a bunch of plants from mail order, and after
> days work, I got them all planted in my 135 gallon aquarium.  My
> question is, though they look great now, they don't seem to be 
> photosynthesizing.  I have 240 watts of lights, and a sandpoint 
> injector, yet a don't see any small bubbles coming from the leav
> any of my plants.  Should I be worried, or is this no big deal,
> could this be a sign of something bad to come.  Plants- a little
> everything; swords, crypts, anubias, bunch plants.

You can't see photosynthesis.<g>  While many of us find the sight 
of O2 bubbles on our plant leaves comforting, remember that the O2 
levels in the tank must be _above saturation_ before you will see 
this phenomenon.  It is perfectly possible for a tank to go along 
happily and healthily (is that a word?<g>) for years without 
streams of bubbles.  Sometimes, if the O2 level is right _near_ 
saturation, you will see tiny O2 bubbles collecting under the 
leaves of broad leafed plants.

The best way to find out if you have enough C02 available for your 
plants is to check it.  This can be done either with a CO2 test 
kit, or even easier, by testing your KH and pH and looking them up 
on the CO2 charts available in any of several places.

IMHO, you're lighting sounds a little on the low side to show a 
lot of O2 action.  I use 6 4' tubes (which is what I assume you 
have?) over my 70G tank.  While it is perfectly possible to 
maintain an attractive tank with the amount of light you are 
using, it's unlikely that you'll see much O2 pearling.

Karen Randall
Aquatic Gardeners Assoc.
Boston, MA