Lookin better.
Be careful with bleach, for 2 reasons: pH effects, and sodium content. If you are in the habit of bleaching, run the system 'dry' with no plants, just plain water, a few cycles to rinse out any residue, and then change the res again before putting the plants back in there.
Peroxide is easier to deal with because it breaks down into water and oxygen gas, while still being effective against pathogens.