Algae Control in freshwater planted aquariums

The Algae Wars (and how to win them)

Left: The planted aquarium owner's best friends! A Siamese Algae Eater (Crossocheilus siamensis) and an Otocinclus catfish (Otocinclus affinis) stand guard over spotlessly clean leaves of Anubias nana. With these little algae war soldiers on duty, algae becomes much less of a problem in the planted tank!

Let's face it: sooner or later, the day comes for every aquarium owner when they look in their tank and discover those green tufts or coating, growing on the plants or glass. Algae strikes again, and perhaps this time it's your tank that's the victim?

Don't panic. Algae can be a nuisance, but it can also be controlled. Notice I did not say eradicated; I said controlled. Despite its bad reputation, algae is just as much a part of nature as any other plant. It is a rare tank that is, and remains, completely algae free. However, it is reasonable to expect to hold algae down to a minimum.

Sadly, many companies market "algae control chemicals," magic potions that are purported to instantly destroy all algae. Unfortunately, most of these chemicals are also very harmful to our desired plants. Some of them are pretty rough on fish, too. It simply is not a good idea to add algae control chemicals to our aquariums.

Algae is a one-celled little plant. Just as the desirable plants in your aquarium, algae also needs pretty much the same things: nutrients and light. If you provide a nutrient rich environment, algae can be expected to grow. Just as desirable plants benefit from iron, potassium, manganese, nitrates and phosphates, so does algae. In other words, when you improve living conditions for your desirable plants, you also improve living conditions for algae.

Well, maybe not. A heavily planted tank with plenty of nutrients, CO2 and adequate light eventually does something that could have been expected all along: it uses up its nutrients. You can prove this to yourself. If you have a heavily planted tank, and if you don't add nutrients, eventually the plants will consume all those nutrients, leaving nothing for the algae to eat. Algae will die without nutrients. Unfortunately, your beautiful plants will also die without nutrients. Let's face it: if you want beautiful plants, you have to add nutrients to your water.

But what if just one vital nutrient is limited in quantity? Let's suppose we add all nutrients except, say, iron. Well, algae needs iron to grow, and without iron it will starve. But then, so will our desirable plants. What about limiting magnesium? Again, algae cannot survive, but neither can your plants.

Probably the best approach is to limit one nutrient that plants need in lesser quantities than algae. That nutrient would be phosphates, with nitrates running a close second. If we limit the amount of phosphate in a tank... limit, but not eliminate... will algae grow? Fortunately for us, the answer is "possibly, but very minimally." In a phosphate-limited environment, desirable plants will out-compete algae, consuming the available phosphates before algae has a chance to get at them.

While you do not want a completely phosphate-free tank, a little phosphate goes a long way for your plants. Therefore, if we restrict the addition of phosphates to the tank, a hostile environment will be created for algae. Fish food contains phosphate, so there is no chance that you will ever achieve a completely phosphate-free tank. However, we must be careful not to add any more phosphate than is required.

Fact is, if you add nutrients without also providing adequate light and CO2 (in the beneficial 10-20 ppm range), algae will grow. You can't just dump in nutrients without also addressing the light and CO2 issues. When nutrients are combined with adequate light (2-3 watts per gallon) and CO2, plants will grow and outcompete the algae. It may take a few weeks, but it will happen.

Growing plants will consume many nutrients. Iron is a mandatory nutrient, but you want to be careful to choose a plant nutrient that has just enough iron, but not enough to create a large surplus. Plants require nitrogen (usually supplied by nitrate, but plants can consume ammonia directly, and thus may prevent the formation of any nitrates in the tank. A few fish in the planted tank (particularly algae eating fish such as Siamese Algae Eaters, Otocinclus, Plecostomus, or other algae eaters) will consume algae while providing ammonia for our desired plants. Any plant nutrients should be carefully chosen to be phosphate free wherever possible. As you feed your fish, you will be putting phosphates in the tank. Other nutrients required by plants that are not known to cause algae growth are potassium.

Recognizing these things in advance, we want to carefully choose a plant nutrient supplement that has moderate amounts of iron, adequate potassium, other trace elements that encourage healthy plant growth, but one which is free of phosphates.

Yamato Green is the ideal plant nutrient supplement that meets or exceeds all of these requirements. Chelated iron is provided at the level of 0.1%, enough for heavy iron consuming plants, but without leaving a lot left over to feed algae. Potassium is abundant in Yamato Green, encouraging the plants to take up iron in an efficient manner. Other important trace elements are there, and in the correct quantities. Sulfur is provided, manganese is plentiful, magnesium is more than adequately supplied. Yamato Green provides exactly the minerals required to encourage healthy growth of wanted plants, which in turn helps those plants to out-compete algae!

Providing adequate light, supplemental CO2, regular daily or weekly dosing of Yamato Green, taking care not to overfeed your fish, and regular water changes to prevent buildup of undesired nutrients are, then, the keys to algae control. It also helps to include algae-eating critters such as Siamese Algae Eaters, and Otocinclus catfish. Other critters that can help would include Plecostomus catfish, but some of the larger Plecos can eat desirable plants as well, so use caution! (Perhaps the best Plecostomus for a planted tank would be the Bristlenose Pleco.) No two tanks have exactly the same number of plants, so individually adjusted doses of Yamato Green will be found to be helpful. Your plants will tell you if you are under or overdosing Yamato Green. If plants remain yellow, or do not seem to be growing as they should (presuming you have adequate light, about 2-3 watts per gallon), then try increasing your weekly dose of Yamato Green. If you notice algae starting to grow on your glass, cut back a little on your Yamato Green dose. By watching your plants, you will soon be able to determine exactly how much Yamato Green will give you magnificent plants, while not encouraging algae growth. The secret to algae control is to control your nutrients, combined with providing adequate light and CO2. With Yamato Green, the nutrient control is easy to attain and to maintain.

USA Flag All Yamato Green chemical products are proudly made in the U.S.A.

Support Our Troops