Updated September 16, 2014
When it comes to maintaining a freshwater aquarium, algae is simply something you are going to have to deal with. Algae require three things in order to thrive – light, carbon dioxide and nutrients. All three of these elements are present in your freshwater aquarium so you should expect to see some level of algae growth in your tank. Though adding algae-eating species of fish to your tank or an aquarium snail
or two might help you to control excess algae growth, there may come a time when you have to take the cleaning into your own hands. When cleaning algae off your tank walls it is important that you exercise caution – you do not want to risk injuring yourself (or your fish) and you also do not want to scratch or crack the glass on your tank. These tips will help you clean the algae off your tank glass safely and effectively.
Safe Cleaning Tips
If your tank goes through an algae bloom or if you simply have a lot of excess algae growth
you may be tempted to simply empty out the tank, scrub it down and start over. Though this option may make sense to you at the time, afterward you may find yourself dealing with unexpected consequences. When you perform such a drastic cleaning of your tank you will likely be destroying most or all of the beneficial bacteria living in your tank substrate. Once you’ve cleaned the tank and refilled it, your tank will need time to reestablish a healthy colony of beneficial bacteria – if you put your fish back into the tank too soon, they could die from ammonia poisoning and you could also find yourself dealing with a bacterial bloom. To be safe, never change more than 25% of your tank volume at once, if you can help it.
When algae begins to accumulate on your tank walls it can severely impact the appearance of your tank – not only does it make it more difficult for you to see into the tank, but it also makes your tank look dirty and unkempt. The easiest way to remove algae build-up from tank walls is to use an algae scrubber. These tools often consist of a rough side designed to scrub at tough algae growths and a sharp edge to scrape it away. In order to use an algae scrubber effectively, work from the top of the tank to the bottom and let the algae you scrape off sink to the tank bottom – when you are finished you can siphon it up with your aquarium vacuum. For stubborn algae growths you might need to use a razor blade. Be very careful when using this option because if you cut yourself the wound could be exposed to the bacteria living in your tank water. To use a razor blade to scrape away algae, hold the blade at a 45-degree angle to the tank wall and gently scrape at the algae.
Preventing Algae Build-Up
If you keep up with your weekly water changes, you should not have a problem with excess algae growth in your freshwater tank. There may come a time, however, when your tank goes through an algae bloom or when, for one reason or another, you fall behind on your maintenance routine. In order to prevent excessive algae growth from becoming a recurring problem, be sure to keep your tank lights
on for no more than 10 – 12 hours per day – excess lighting could result in increased algae growth in your tank. You should also be sure not to feed your fish more than they can consume in a few minutes because anything they do not eat will simply sink to the bottom of the tank where it will provide nutrients for algae to grow. As mentioned earlier, adding an aquarium snail or an algae-eating species of fish
to your tank will help to keep algae build-up under control and maintaining high water quality in your tank will be beneficial as well.
Useful Algae Eating-Fish
Another option in removing algae from tank glass that doesn’t involve any extra effort on your part is simply to add some algae-eating fish to your tank. There are a number of different species of freshwater fish which can be used as algae-eaters in the home aquarium including the following:
- Bristlenose Plecostomus
- Siamese Algae Eater
- Twig Catfish
- Rosy Barbs
- Flag Fish
Certain species of crustacean such as snails and Amano shrimp can also be very effective as algae eaters. Bristlenose Plecos are very easy to find and they are highly effective as algae eaters as well. Keep in mind that these fish can grow fairly large and that they require supplementation with plenty of fresh greens and algae tablets in addition to the algae in your tank. Siamese Algae Eaters are hardy fish that eat several types of algae as well as flatworms, a nuisance which many fish ignore. Twig Catfish require very large tanks and they can be fairly sensitive to changes in water parameters. Otocinclus are a small species of catfish which do particularly well in planted tanks, especially when kept in groups with others of their own species. If you choose to use algae eaters in your tank, be sure to research them first to make sure they are compatible with your other fish and with the parameters in your tank.
Algae is a fact of life for aquarium hobbyists and, while you cannot completely prevent it from growing in your tank, you can do your best to deal with it responsibly when it does.