"E. Mito" wrote:

I may decide to setup a small DIY CO2 injection
system if the riccia doesn't start growing...it's looking a little shabby and I
haven't noticed much pearling.

You may want to try some Flourish Excel first. I was pretty doubtfull
with 'CO2 in a bottle', but decided to try it for a few dollars. I have
seen a difference in my small plant tanks.