Troubleshoot
Aquarium Algae ID Chart: BBA vs Hair vs Staghorn (+ more)
Wrong ID wastes weeks. Use look + feel: dark brush, green strings, antlers, hard spots, dust film, brown powder, slime mats, or pea-soup water—then open the matching fix page.
- Algae ID
- BBA vs hair vs staghorn
- Look + feel
- Jump to fix
What you’re seeing
Start here before chemicals. Match the row, then follow the linked playbook.
| What you see | Feel / wipe test | Name | Go to |
|---|---|---|---|
| Dark short tufts on wood & leaf edges | Wiry, doesn’t wipe | BBA (black beard) | BBA fix order |
| Long green filaments waving | Soft, twirls on a stick | Hair / thread | Hair algae |
| Grey-green / rust antler branches | Firner than hair | Staghorn | Staghorn |
| Woolly green blanket on wood | Coarse, clings | Cladophora | Cladophora |
| Hard green dots on glass/slow leaves | Scrapes, doesn’t smear | Green spot (GSA) | GSA |
| Soft green film on glass | Finger streak wipes clear | Green dust (GDA) | GDA |
| Brown powder on glass/sand (new tank) | Dusty wipe | Diatoms | Diatoms |
| Slimy blue-green sheets on sand | Peels as a mat, may smell | Cyanobacteria | Cyano |
| Whole water pea-soup green | Flashlight beam is green | Green water | Green water |
Parent field guide: algae control hub.
Likely causes (ranked)
Name mix-ups in hobby groups
“Black hair” might be BBA or true hair—look, don’t trust the nickname.
Quick test: Someone said black hair but tufts are brushy on wood.
Treating all green the same
UV helps green water, not BBA tufts on wood.
Quick test: Bought UV for hardscape brush algae.
New-tank brown vs later green
Month-one powder is usually diatoms, not a reason to dose algaecide.
Quick test: Tank <6 weeks, brown dust.
Skipping the wipe/flashlight test
Film vs soup vs tufts need different first steps.
Quick test: No wipe test before buying chemicals.
Fix order
-
Step 1
Do the two tests
Wipe glass (film vs hard spots). Flashlight through water (green soup vs clear). Pinch a tuft (soft string vs wiry brush vs antler).
-
Step 2
Open only one playbook
Use the table above. Don’t run blackout + bleach + UV + EI dump on the same day.
- Step 3 Fix the shared drivers
-
Step 4
Re-check in 7 days
If the look changed (hair became slime mats), switch pages—don’t stay on the wrong guide.
When to escalate
- Still unsure after tests → photo the tuft on white paper (macro) and compare rows again.
- Multiple types at once → treat the dominant one first (usually light hours + organics), then the leftover ID.
- Tools → calculators.
Helpful products
Related guides
- BBA — Dark brush
- Hair algae — Filaments
- Staghorn — Antlers
- Algae hub — Parent
FAQ
Why not one “kill all algae” product?
Different organisms. UV clears green water; it does nothing to BBA on wood.
Is black hair algae BBA or hair?
If it is dark and brushy on edges/wood → BBA. If it is long green strings → hair, even if someone nicknamed it black.
Can two types grow together?
Yes—e.g. GDA on glass + hair on stems. Fix light hours first; it helps both.
Do I need a microscope?
No for this chart. Look + feel + wipe/flashlight is enough to pick a playbook.
Where do I start if everything is green?
Flashlight: soup → green water. Glass wipe: film → GDA. Tufts on wood → BBA/staghorn/Clado table.
Is brown always diatoms?
In month one, usually yes. Later brown slime that peels and smells → suspect cyano.
Aqua Plants Hub Editorial
