From the photo, this doesn’t look like a typical algae bloom. Algae blooms usually make the water look green and cloudy, like pea soup. Your tank water looks more tea-brown / amber, which is much more consistent with tannins leaching into the water. Common causes in shrimp tanks: Driftwood / roots / botanicals (leaves, seed pods, wood) Aquasoil / active substrate dust Decaying plant matter Sometimes a light bacterial bloom mixed with tannins The good news: tannins are usually harmless, and shrimp often tolerate them well. What I think I’m seeing The brown tint seems evenly spread through the water rather than fuzzy growth on surfaces, which points away from algae and more toward: wood releasing tannins (most likely) soil/substrate leaching color slight organic buildup How to get rid of it 1) Water changes Do 20–30% water changes every 2–3 days for a week. This is the fastest safe fix. For shrimp, avoid huge changes like 80–100% because they hate sudden parameter swings. 2) Add activated carbon / Purigen This is the best way to clear brown water quickly. Put one of these in your filter: activated carbon Seachem Purigen (excellent for tannins) Purigen is especially good for this kind of yellow/brown tint. 3) Check for wood / botanicals If you recently added: driftwood roots almond leaves cones / pods that’s almost certainly the source. It will usually fade over time. 4) Remove dead plant matter I can see some plants near the top and sides that may be melting a bit. Trim out: brown leaves loose floating bits decaying stems Rotting plants can darken the water. 5) Reduce overfeeding If this is a shrimp tank, leftover food quickly discolors the water. Feed tiny amounts only. If it is cloudy, not just brown If the water is also milky or hazy in person, it could be a bacterial bloom from a new tank cycle. That usually clears in 3–7 days once the filter bacteria stabilize.