Algae (pronounced AL-jee) are simple forms of marine plant life. They’re pretty basic: they lack leaves, roots, flowers, seeds, and all the other things we normally associate with plants. The term ‘algae’ is an umbrella phrase that’s used to refer to all forms of marine life that are capable of photosynthesis (converting sunlight into energy), although some forms of algae rely entirely on external supplies of energy (in the form of protein and fish waste in the water) for food.
As far as your tropical fish tank goes, algae is definitely an unwanted visitor – it’s a real eyesore. Of course, certain levels of algae are to be expected; small amounts are inevitable wherever there’s light, nutrients, and water in combination.
However, when levels get high enough to be visible to the naked eye, you’ve got a surplus.Unless you maintain your aquarium regularly, you can pretty much count on regular growths of algae obscuring your fish, making the water smell, and generally detracting from the aesthetic appeal of your tank.
White spot is usually introduced to a tank along with new, infected fish or plants. It can also break out seemingly without warning in an undisturbed tank. When this happens, it means that the organism has been present for some time, but has been dormant (hibernating), and that some new stimulus – stress, or a change in water temperature – has caused it to awaken and become active.
Limiting the light available won’t make any difference to this type of algae, since it’s perfectly capable of growing at low-lighting levels. Instead, you need to cut right back on the nutrients available for sustaining its growth – which means feeding your fish less. High protein levels in the tank, derived from fish food, will fuel this algae’s growth.
Unfortunately, choosing fish for an aquarium isn’t as simple as you might think. You can’t just go into a pet store and select arbitrary numbers of the fish that you find the most appealing – you need to invest some forethought into your tank to ensure that your fish lead happy, healthy lives.
These “daughter cells” will then break loose and swim freely about the tank, attaching themselves to new fish – and beginning the cycle all over again. White spot is highly contagious and progresses very rapidly. 100% mortality is to be expected unless something is done about it.
Green algae will appear in just about any tank with plenty of light. Fortunately, it’s easy to remove (it doesn’t cling to the glass too much) and most algae-eaters will consume it with gusto.