I Just Had A Bad Hair Algae Day

In a planted aquarium, any outbreak of algae can be attributed to an imbalance between the three essentials for the promotion of plant-life.

There needs to be a balance between light, nutrients and carbon.

An excess or lack of any one of these elements can be responsible for an algae bloom.

The difficulty is understanding where the imbalance lies.

The way to discover which, is to change one thing at a time and observe results.

Now, if you suspect something in your tap water may have changed, then as long as it reverts back to previous parameters balance will return and your algae should die off.

One of the simplest and most often overlooked method of controlling algae is to increase the fertiliser you provide your plants with.
It might sound counterintuitive but, if you can switch on your plants to increase their metabolism, they should out-compete the algae and it will die off.


NOTE: The above only relates to planted tanks.
In tanks with no live plants the only plant-life that can benefit from light + nutrients + carbon is always Algae.

Funnily enough, on the well-known planted tank forums they usually advocate injected CO2 as a method of combating algae.

I tend not to recommend it as, a) I don't use it so have no personal experience, b) it's an expense and complication that many aquarium keepers don't want and c) it's only 'necessary' if you're keeping a high-tech setup with plants that need a high-tech environment.

FWIW I use liquid Carbon, but I only grow low-tech plants.

Thank you Simon, I just had a quick google and I also saw a references to Algae not doing so well at lower pH values so that probably concludes it - It was the removal of the CO2, slowing plant growth, a drift up in pH and day length increasing that gradually favoured the algae.
That or it was the butler, never trusted him don't you know - eyes way too close together and the blighter came from Brighton.