I never know what to say during videos so hopefully the background music will cover up any heavy breathing
Bacopa caroliniana should be fine as a background plant. You can trim those star repens; I find a pair a scissors works with small plants such as these. If you need more give me a shout. I may be trimming mine in a week or so and I have no room for the trimmings.
When you start with DIY CO2 you might want to remove/plug the air line that feeds the power head. The agitation will remove some of the CO2 you are adding. You may not see the benefits of CO2 right away; it took several weeks for my plants to respond.
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