[gpodio]

2-4WPG for a 20g tank is quite good however know that it will require CO2 or excel at these light levels. Thought I'd mention that just in case you are not currently using CO2, the upgrade will certainly change the requirements of this tank so prepare for those as well.

Hope that helps
Giancarlo

 

[gpodio]

Just a personal opinion here but the Hagen CO2 system is not really a comprimize between DIY and Pressurized, I see it as DIY without having to drink the coke out of a bottle The two are just as consistent in my experience. Flourish Excel is another option.

Hope that helps
Giancarlo Podio