Tired of your bird bath turning green too quickly? Here is a helpful guide on how to seal your cement bird bath to ensure no algae grows on it and you can attract lovely birds into your garden.

First of all, before applying any sealer to the birdbath, it must be absolutely clean and free of any spores, loose debris (including perhaps any powdery cement).


  1. Empty the birdbath and, we suggest, allow it to dry completely in direct sunlight so that the algae begins to flake or at least becomes powdery.
  2. Use a stiff-bristle scrubbing brush to thoroughly scour the entire surface of the birdbath to remove dry algae and any other debris.
  3. Fill the birdbath about ¼ full of water and use the brush to remove any embedded dirt. Empty the birdbath again and then use the brush to clean any stained area or any algae from the surface with a mixture of ¾ cup bleach in 5 litres of warm water. Discard that water once you have cleaned the surface thoroughly.
  4. Finally, fill the birdbath to the brim with the same bleach mix (make extra if necessary) and allow it to stand for about 15 minutes or so before emptying it out. Give the surface a final scrub, rinse the surface with clean water and allow it to dry thoroughly. By now any trace of algae should be gone.

We have gone on a bit with the cleaning aspect, but the cleaner the surface is, the less likely there will be any algae spores on the surface and the better the sealer will adhere.

Now for the pond sealer: we have shown two types which have been formulated to be suitable for koi ponds, water troughs, water features and so on – so they should be safe for birds as well.

Durapond is the more expensive of the two products at around R300 for a litre. It is a polyurethane pond sealer ideal for livestock water troughs, water features, planters, pot plant containers and fish ponds. It forms a non-toxic waterproofing barrier that withstands permanent immersion in water. It is fish friendly and non-toxic, odourless, flexible and durable, and is available in black and blue.

Super Laykold is a less expensive product (available in black), at around R150 for a litre and formulated to be ideal for koi ponds and therefore should be safe for birds.

Whichever product you select, follow the application instructions and allow it to dry completely before filling the birdbath with water.

Note that a sealer may need to be reapplied every two to three years.

There are a number of algaecides available but generally these are from pet shops that sell fish and aquatic products, or dedicated shops specialising in selling tropical fish (most usually, but some might also sell marine fish).

Generally it should be safe to assume that if a product is safe for fish, it will also be safe for birds.

Mica stores are very unlikely to carry such products so we suggest that you contact pet shops in your area for advice on what algaecides are available and to also confirm at the same time that the particular products under discussion or that they recommend, are safe for birds.

Alternative anti-algae measures:
As an alternative to using bespoke products, as an alternative you might consider the following:

We have found that copper, which is a natural algicide, can help keep algae at bay in a birdbath. You can use a small length of copper pipe or tubing, or a copper plumbing fitting (available from any Mica store), or even a brass key for which you have lost the lock it used to operate. As far as we could discover, there is no clear evidence that copper is toxic to birds, though toxicosis can occur in wild bird populations.

However, a low concentration in a birdbath should not be harmful; but if in any doubt whatsoever, avoid this method. (In any event, never use copper as an algaecide where fish are concerned – it is toxic.)

Safe, and environmentally safe methods appear to be:

  1. Adding 1 capful of apple cider vinegar will keep a birdbath clean and reduce algae growth. It also provides vitamins & minerals to the birds
  1. Keep the water shallow, no more than about 50mm in the middle.
  2. Add a couple of rocks so that the birds have extra ‘jumping-off’ positions.
  3. Ideally the bottom of the birdbath should be rough, not smooth… cement is fine. The reason is that birds don’t like to lose their footing; it makes them feel unsafe. They don’t like a glazed, slippery bottom when taking their ablutions.
  4. Position: position the birdbath a couple of metres at least away from any bush or other structure than can provide concealment for a predator. A good location is under some branches that hang down within 600mm to a metre above the bath so that a bird that feels threatened can quickly fly up to safety.

Finally, here are some indigenous plants that attract birds to your garden:

  1. Acacias. Weavers love acacia trees and there’s no better way to add that African feel to your garden
  2. Aloes are perfect for attracting nectar-eating birds and what’s more aloes are drought tolerant and water wise
  3. Cape honeysuckle
  4. Coral tree
  5. Cross-berry
  6. Ericas
  7. Fuchsias
  8. Hibiscus
  9. Pincushions
  10. Proteas
  11. Red hot pokers
  12. Strelitzias
  13. Tree fuchsia
  14. Watsonias
  15. Weeping boer bean
  16. White stinkwood

The reason we have included a list of plants is that the more holistic your approach, the more birds will be attracted to your garden, and plants that attract insects will in turn attract birds (insect-eating), as will plants that produce nectar – which will also attract birds and they will all probably want a drink and/or a bath at some stage!

We hope that it will help you to avoid that algae-infested birdbath, and that you will soon have more birds in your garden than your neighbour has.