There are some dangers involved with many methods.
How many cases of aquario gasing their fishes with injected co2? I think that probably it did happen at least one time for many experienced aquarists who does.
Cases of blowing bottles with diy co2 yeast/sugar.
I do not say not to inject co2 though. If co2 would become more affordable in my area, i would be back using it.
As for me after 21 months of injecting co2 i did stop and return to using Seachem Flourish Excel, and quite happy about it. I will buy a 2 liter soon,
Excel is an isomer of glutaraldehyde, not quite exactly glutaraldehyde, it is more stable, stays active for 24 hours, glutaraldehyde stays active 12 hours maximum.
Michel.