If you add co2 you will have to find a balance between nutrients, light and co2.
for co2 you shout at 30ppm, if you have surface agitation going your fish shouldn't have a problem with the co2.
look into diy co2 to try it out.
If you want to go the pressurized co2 way, I would say, research and read, read and read some more and then have a big wallet ready. I spend months researching it before I tried it.
IBC and Shelve Aquaponics
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125g Breeding group Tilapia
2x 75g+ 40B Tilapia outgrow tanks
20H Philippine blue Angelfish breeders + fry
20L CPD and Shrimp tank
10g Apisto Gibbiceps
Savannah Cat: Kimchee