Took atomizer off now and replaced with my old ceramic diffuser .
Running at about 2-3 bps now right under a new wave maker 2000l/hr ,added to get the tank water moving a bit better . Took drop checker straight to yellow , but fish and shrimp don't seem to be bothered at all. got a week off work so i can monitor levels closely and adjust as needed .
No pics of the main tank , but here's a few of my shrimp tank ,no CO2 and its occupants.

had theese shrimp a week and they have berried up already
edit - Just purchased another 5 x Crystal Red shrimp ss+ grade Double Hinomaru to get some nice babies
looking for some black crystals also