Algae is normal in aquariums, but heavy algae usually means the tank is getting too much light, too many nutrients, or inconsistent maintenance. The good news: you can fix most algae issues without harsh chemical “quick fixes” that stress fish or crash stability.
Why algae shows up
- Too much light: long photoperiods or direct sunlight are common triggers.
- Excess nutrients: overfeeding, rotting plant mass, or heavy waste load.
- Inconsistent maintenance: letting detritus pockets build, clogged filters, or irregular water changes.
The simplest plan that works
- Set lights to 6–8 hours and keep the schedule consistent.
- Reduce feeding slightly for 7–10 days (especially rich foods).
- Add plant mass (easy plants and floaters compete with algae for nutrients).
- Do routine water changes (20–30% weekly) and target detritus pockets.
Mechanical removal (without stripping the tank)
Scrape glass, remove algae strands by hand, and siphon debris during water changes. Avoid “sterile resets” where you deep-clean everything at once — that often causes a new algae wave because you destabilise the tank.
Clean-up crew: what’s realistic
Snails and shrimp can help with some algae types, but they don’t replace the plan above. If you add a clean-up crew while overfeeding and running lights 12 hours, algae will still win.
When algae is a symptom of something bigger
If algae appears right after you “improve” lighting or start heavy fertiliser dosing, scale back. In guppy tanks, fish waste often provides plenty of nutrients for easy plants. Stability beats maximum growth.
Think of algae as feedback. Adjust light, feeding, and maintenance, and the tank usually settles into a cleaner, more balanced state within a few weeks.
