Recovering from low oxygen

Increasing the air input yesterday seems to have helped the tank to regain it's balance. I did the water quality tests just before a 20% water change and the Nitrite was back to zero. I can only assume that lowering the air input lowered the oxygen (hence the shrimps at the top of the tank with the Guppies and the Danios being a lot quieter) and this affected the bacteria also. Makes sense, I suppose.

Unfortunately, the shrimp is no longer carrying eggs. Even I am not optimisitic enough to hope they all hatched and are hiding - I think that she was removing them yesterday as I was trying to recover the oxygen levels. Maybe as the Oxygen dropped the levels got too low for the eggs and they died - just days before they should have been ready to hatch.

Unfortunately, it also looks lile the white spot is back! The halfbeak seems clear - he usually shows new spots on Wednesdays though so we'll see tomorrow. This time two of the Neons seem to have tiny whitespots. Will I ever get the tanks sorted and running happily?