Why do you think you'll have to replace the macrandra and glandulosa because of co2?
Mine does great with co2.
I reread your post and I think I originally misunderstood .
You think they'll die off before you get the co2 going.
I grew both of these plants without co2. It's very slow growth but they did grow and multiply.
Last edited by Chaoslord; 09-08-2012 at 02:32 PM.
Reason: added edit after rereading post.