Algae, the Wonder Plant
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Where you find a healthy body of water you’ll find algae,
often mistaken for bad bacteria or fungus; grunge. Goldfish make waste, from
which ammonia forms, and within a short time is converted to nitrite, and then
into nitrates by beneficial bacteria. Nitrates are the food source for algae,
and forms with little encouragement if conditions are right. A healthy food
source for fish, they eat the algae, produce waste, and the cycle of life begins
In an established tank or pond you may notice the water is turning green; known as green
water algae or you may see free floating algae at your pond's surface; known as string algae, or you may notice a build-up of algae on the sides of your tank or pond; known as substrate algae.
Some forms of algae unintentionally suffocate or eliminate oxygen from water; some by covering the surface area, such as string (blanket) algae. Some species of algae reduce oxygen levels in the water just because they take up space; rapidly reproducing, pushing oxygen out of the water, such as green water algae. These forms produce dangerous conditions for goldfish and beneficial bacteria alike. The only safe form of algae for goldfish is 'substrate' algae.
- How to grow algae
Goldfish love to nibble on algae and it
is a very healthy snack for them, providing a rich source of nutrients and
roughage. Goldfish have been known to live off nothing but algae, and be all the
healthier for it.
Requiring only low levels of lighting, a plant light or natural sunlight combined with the presence of nitrates must be present to encourage algae growth. In a cycled tank nitrates are the last of the toxins to convert. Algae feed on nitrates, creating a balanced ecosystem by reducing or eliminating it completely. Only cycled tanks and ponds have algae.
· How to eliminate green water
Free floating, green water algae cannot
tolerate moving water. If you have green water your fish are at risk for
suffocating. Including a pond pump to your set up will clear the body of water,
forcing the algae on to substrate.
Water treatments convert nitrates to a safer form, but algae can still feed on the toxin. If you don’t appreciate the look of it in your glass aquarium use an algae scraper to remove it from the front and sides of the tank, but leave it growing on the back. Another method of reducing algae formation is to add several plants to the aquarium or pond to increase the competition for nitrates.
If you want to increase the levels of algae in your tank or pond, allow nitrates to increase gradually by using water treatment specifically designed to convert the toxin. Gradually reduce the amount of water you’re exchanging over an extended period of time, and the algae will grow gradually also, reducing nitrate levels, offering a low maintenance set up. No other plant can compete with algae in nitrate reduction.
Algae is either green or brown in colour. It appears darker brown when submerged beneath water where the light may be dimmer
- The color of algae
You may hear folks talking about orange,
pink or red algae, yellow, blue or even white algae, but this isn't actually
algae; it's fungus that has taken on a few characteristics of algae. The only
similarity is both are made up of living organisms. Algae is green or brown, and
found only in healthy ecosystems that contain nitrifying bacteria. Algae
contains chlorophyll, consumes nitrates and is a healthy food source, unlike
If the algae in your tank or pond is any colour except green or brown; it’s not algae. Eliminate it by performing the salt treatment, but in order to eliminate it permanently, a healthy ecosystem must be created. Increase oxygen levels by adding a pond pump or two. Check your freshwater source for bad bacteria.
Algae feeds on nitrates and provides a very nutritious
meal high in roughage
In the wild competition for food is fierce. Only the fastest or the luckiest fish feeds on caviar, small fish or worms. Because of it, goldfish feed mostly on vegetation even though they are omnivores.
In a natural body of water you won’t see fish bobbing at the surface, suffering from floating issues caused by constipation; this is because they eat small amounts consistently throughout their waking hours, and most of their diet consists of algae and other nutritious vegetation, such as duckweed, running a close second to algae in value. Their diets are very high in roughage.
The circle of life in the world our goldfish live in may very well begin and end with plants. The goldfish eat vegetation which turns to waste, which turns to ammonia. Beneficial bacteria form to feed on it producing nitrite and then nitrates. Nitrates are the food source for vegetation. Our goldfish feed on the vegetation, creating more waste.
Algae, made up of microorganisms or diatoms, contain protein. The levels of protein are just right for goldfish; not so high that it raises nitrates, but high enough to provide the protein levels that fish need for good health. Goldfish can live off nothing but algae, and be all the healthier for it. Algae has all of the vitamins and minerals goldfish need. Of course, if we don’t supplement their diet with some peas or flakes, being in a small container, they would consume all of the algae in a short time.
This stock tank has green algae on the sides up to the water line, but the algae is brown closer to the bottom because the lighting levels are lower
It’s okay to feed goldfish worms or shrimp, but only
periodically, and in very small amounts. It’s also fine to feed food gel; very
nutritious, and an excellent method of treatment. Gelatin in itself is nothing
but protein. This is why we recommend feeding for short intervals and sparingly.
Some species of algae reduce oxygen levels in the water just because they
take up space; rapidly reproducing, pushing oxygen out of the water, such as
green water algae. These forms produce dangerous conditions for goldfish and
beneficial bacteria alike.
The only safe algae for goldfish is 'substrate'
If you have green water algae, increase your water movement or action and within weeks the green water algae will turn to substrate algae
How to grow algae
Goldfish love to nibble on algae and it is a very healthy snack for them, providing a rich source of nutrients and roughage. Goldfish have been known to live off nothing but algae.
Requiring only low levels of lighting, a plant light or natural sunlight combined with the presence of nitrates must be present to encourage algae growth. In a cycled tank, nitrates are the last of the toxins to convert. Algae feed on nitrates, creating a balanced ecosystem. Only cycled tanks and ponds have algae.
Water treatments convert nitrates to a safer form, but algae can still feed from the converted nitrates. Unless you have a thick lining of algae, nitrates must be removed by means of fresh water changes, but do so gradually. When you remove nitrates from the water, you're also removing ammonia; the food source for beneficial bacteria. Just because we can't measure ammonia, doesn't mean it's not present. The toxin is being converted as it's being produced.
Algae is either green or brown in color. It appears darker brown when submerged beneath water, but at the top of the water line you may notice it's much greener being closer to the light
- What color is algae?
You may have seen or heard folks talking about pink or red algae, yellow, blue or even white algae, but this isn't actually algae; it's a harmful bacteria that have taken on a few characteristics of algae; fungus, and is found only in a poor ecosystem whereas green algae is found only in healthy one. Algae contains chlorophyll, and feeds on nitrates, unlike bad bacteria. Algae is also a food source for goldfish, unlike fungus.
Although we consider the three toxins to be the nitrogen cycle as a whole,
algae, along with other vegetation that feed on nitrates may be considered as
the icing on the cake, completing the circle of aqua life. The goldfish feed on
the algae, producing waste that feeds the beneficial bacteria who in turn
produce nitrates that feed the algae.
If the algae in your tank or pond is any color except green or brown; eliminate it by performing the salt treatment, but in order to eliminate it permanently, a healthy ecosystem must be created. Increase oxygen levels by increasing water movement in your goldfish house. Harmful bacteria cannot tolerate heavily oxygenated water.
Some of these rare forms of bacteria require intense lighting for extended periods of time. This is why they are more commonly found in warmer regions. Remove artificial light source, and lower water temperature temporarily. Check for phosphates in tap water. Some of these forms thrive in water high in this mineral or chemical form; either one.
Since we know that algae feeds on nitrates, we can assume that having algae in a tank or pond keeps nitrate levels low providing a safer environment for goldfish. Dangerously high nitrate levels oxidize the iron atoms in hemoglobin, reducing oxygen supply to the blood stream and tissue. This condition is called Methemoglobinemia; closely related to the effects of DCS. This condition is typically fatal and may also cause bent positioning in goldfish. Nitrite poisoning causes a similar condition
Curled or Bent Positioning
Whether you keep your fish in an aquarium or pond, algae is the goldfish keeper's best friend.