I have now reduced CO2 to 1 bubble per second (although I think the drop checker is giving a false reading as it has remained yellow for days).
Purchased amano shrimp. I will grab an otto tomorrow.
I'll run my nitrate/nitrite test tomorrow too and try to pick up a phosphate kit this week.
Lighting is difficult to move. I notice this algae is still growing and bubbling int he corners which don't get too much light. I'm not sure what that is all about.
I'm dosing Vimi all-in-one with micros and macros. One pump every 2 days (as my tank probably only has 25l capacity). Details here:
Thanks for the help.