28w over 125L tank isn’t a lot of light, It’s highly unlikely you are CO2 limited. I doubt you’ll benefit at all from pressurised CO2.
Those plants fall into the easy category and don’t need a lot of light. How old are they?
It’s normal for plants to melt back when they are first put in a tank and can take some time to become established.
‘Liquid CO2’ is a good algaecide which would explain the algae reduction when using it.
If the plants are fully established my guess would be either:
Your plants aren’t getting enough nutrients.
There’s too many waste organics in the water fuelling the algae.
It’s difficult to tell without knowing exactly what is going on over time. Im sure others will chime in shortly with some ideas.
Those plants fall into the easy category and don’t need a lot of light. How old are they?
It’s normal for plants to melt back when they are first put in a tank and can take some time to become established.
‘Liquid CO2’ is a good algaecide which would explain the algae reduction when using it.
If the plants are fully established my guess would be either:
Your plants aren’t getting enough nutrients.
There’s too many waste organics in the water fuelling the algae.
It’s difficult to tell without knowing exactly what is going on over time. Im sure others will chime in shortly with some ideas.