updated July 2020


Algae is so prevalent in the hobby that for many, it seems almost inevitable and a natural part of a planted tank. This is not the case. Through thousands of interactions with fellow aquarists, the most common 'root cause' is poor housekeeping (build up of decaying leaves and organic matter) and the second 'mistake' is in under-injecting CO2 (while having strong lighting and growing demanding plants) which result in unhealthy plants- and giving algae, which is very opportunistic, the ideal environment to grow. A detailed exploration of the subject is covered here.

For housekeeping, regular water change (every week, or at the very least every 2 weeks) is key. This removes organic matter and helps reset imbalances that inevitably builds up in the tank's closed ecological system. A handy water-change tool is indispensable. As part of housekeeping, a pair of LONG TWEEZERS and LONG SCISSORS are also necessary to trim and remove dead and decaying leaves. A simple but powerful hack in housekeeping is the use of a TURKEY BASTER to stir up debris before 'vacuuming' the substrate surface as part of my regular water change. This is akin to flossing in preventing tooth decay: simple and hugely effective.

densely planted low tech tank

Above: one of the simplest and most effective defence against algae is to plant densely, which immediately creates an environment where the plants easily outcompete algae. Sparsely planted tanks are comparatively much harder to keep algae-free.

Water Change / Maintenance Tools

  • An indispensable tool for proper substrate cleaning is the humble TURKEY BASTER. We use it to stir up the debris on the substrate while doing our fortnightly 30%-50% water change. Check out the video here.
  • A tool such as the PYTHON WATER CHANGER makes this otherwise tedious process much easier. Regularly changing 30%-50% of a tank's water is an often neglected, but hugely important routine, for removing organic waste, the #1 algae trigger.
  • LONG SCISSORS & TWEEZERS are necessary tools to remove dead and decaying leaves, a prime algae magnet. 
  • A UV STERILISER is a 100% cure for green water. Read more about algae types and green water here. It does not remove all types of algae. However, also useful for some forms of water parasites.
  • This SCRAPPER with an extendable handle makes it easy to accommodate both a shallower and a deeper tank.


  • To kill stubborn patches of algae (BBA, Cladophora), one can use HYDROGEN PEROXIDE (3% concentration), using an eye-dropper tool (see below) to spot dose directly onto algae. Be careful not to exceed 1ml per gallon as livestock can be affected.
  • SEACHEM EXCEL is marketed as a workaround to injected CO2 but it is widely used by experienced aquarists for another reason- for spot-treatment of algae. Read more about it here. It works similarly to Hydrogen peroxide but some plants are more susceptible to it (liverworts, vallisneria species). The advantage of Excel is that it can be stored for long periods. Hydrogen peroxide degrades to water and oxygen over time. This can be used as a dip solution when diluted in a 1:25 ratio. Dip plants affected by algae in the mixture for 20 seconds.
  • For serious filamentous algae, API ALGAEFIX is a strong nuke. It should not affect fish if dosed accurately according to instructions, but it will kill shrimp.
  • For specific treatment of persistent BGA / Cynobacteria problems, CHEMICLEAN and the ULTRALIFE stain remover work well.
  • EYE DROPPERS are useful for spot dosing algicides onto problem spots. H2O2 and Excel should always be spot dosed (vs. simply pouring the contents into the tank).

Tools to enhance biological maturity

Well cycled (biologically matured) tanks are far more resilient to algae and we would recommend good tank cycling before adding livestock (which will contribute to organic waste, the the #1 algae trigger). API QUICKSTART is good to kickstart tank cycling. This reduces cycling time to less than a week even when using ammonia rich substrates such as ADA aquasoil. (still need to do required water changes for first week though). SEACHEM STABILITY works in the same way.

No products found in this collection