Cloudy white / grey — new tank
This looks like: bacterial bloom while biology finds its balance — ugly, often normal, not magic evil slime
Why this happens
Bacteria that eat dust and food explode before your nitrogen team is fully staffed. That haze is biomass in the water column, not necessarily poison by itself.
How sure are we? Very high in week 2–8 setups.
What to do right now
- Test ammonia anyway — bloom plus ammonia hurts.
- Feed lightly — almost boringly light.
- Avoid cleaning the filter spotless — seed bacteria live there.
- Small water changes only if ammonia demands — massive water swaps rarely erase blooms faster.
- Patience plus test discipline — log numbers in App-aquatic so you see the curve.
What not to do
- Don’t buy “instant cycle” hope in a bottle without reading ammonia daily for a week.
If that doesn’t fix it
Green instead of white? That is algae, not this bloom.
Catch this earlier next time — log your water parameters in App-aquatic. Free forever.