Anyone know why this is?

Ben2522

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Hi, this has started growing on decorations and now on glass. What is it? On image looks brown but is more of a dark green to the eye.
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Colin_T

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the black stuff is black beard algae.
the green stuff on the gravel is blue green algae (Cyanobacter bacteria).

take the rock out and scrub the algae off.
do a 75% water change and gravel clean the substrate every day for a week to get rid of the blue green.
make sure any new water is free of chlorine/ chloramine before it's added to the tank.
 
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Ben2522

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the black stuff is black beard algae.
the green stuff on the gravel is blue green algae (Cyanobacter bacteria).

take the rock out and scrub the algae off.
do a 75% water change and gravel clean the substrate every day for a week to get rid of the blue green.
make sure any new water is free of chlorine/ chloramine before it's added to the tank.
Hui. How to get rid of the black beard?

The Bluegreen algae, Th substrait is fine gravel so cant clean it. Hoovered twice this week bit it comes back 24 hours later and more of it.

Any natural solutions?
Thanks
Ben
 

utahfish

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Algae is a sympton of a wider range of problems.
Algae needs a few things to grow in limited amounts. Light, water, and nutrients. If too much of any of these 3 algae will take over.
Algae needs around 8 hours of continuous light to grow, by limiting light for under 8 hours algae is limited. If one doesnt have live plants all light is doing is growing algae, that includes light outside the tank from windows or light fixtures. Try covering tank with something when light isnt on to keep unwanted light out.
Nutrients. In nature algae competes with live plants for nutrients and light. If one doesnt have live plants the nutrients in water are only feeding algae. If one does have live plants then algae will take hold in the presence if too many nutrients, or not enough nutrients for plants. Effective way to limit nutrients, frequent large water changes. Decrease feeding. If one is feeding twice a day switch to once if once a day go every other day. If have plants then one may be deficient in one or more of the 17 nutrients plants need to grow in which case algae takes hold. Effective fix get a comprehensive fertlizer that provides all 17 essential nutrients to plants and dose accordingly.
As for cynobacteria. Or blue green algae. It thrives in anaerobic warmer well lit nutrient rich environments. Turning temp down will cull not eliminate cynobacteria. Low end of tropical range is around 75 degrees. Temps in high 70s or 80s encourage bacteria. Cooler water also contains more dissolved oxygen. Low oxygen levels encourage cyno bacteria and lastly excess light and organics. Decrease length of light decrease feeding and increase water changes to decrease excess organics in the water that contribute to algae.
Good luck!
 

utahfish

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Hui. How to get rid of the black beard?

The Bluegreen algae, Th substrait is fine gravel so cant clean it. Hoovered twice this week bit it comes back 24 hours later and more of it.

Any natural solutions?
Thanks
Ben
Also if using tap water check your local water municipality for levels of phosphates and nitrates and other organics. If say ones source water has 20ppm of nitrates then algae in the absence of plants will glad take advantage of those excess nitrates as well as phosphates. Adding water during water changes that is high in nitrates and phosphates and other organics is counter productive to the purpose of water changes. To mitigate this one could mix tap water with RO water to dilute the nitrates and other excess organics in ones source water and or add fast growing plants to absorb nitrates and other excess nutrients, hornwort, anacharis, duck weed, frog bit, wisteria to name a few
 

Byron

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I have battled both over the last decade, and my comments will generally follow other members. First as noted, you are dealing with two issues, though they are similar with respect to the causes.

First the cyano as it is easiest. Cyanobacteria is caused by organics in the presence of light. Prevention is easy once you get the tank's biological system "cleaned up." Weekly substantial water changes (50-70% once each week), cleaning into all open areas of the substrate (organics accumulate in the substrate and are essential for a healthy biological system and they provide plant nutrients but they need to be kept in check), keeping the filter well rinsed, not overfeeding, not overstocking (too many fish, and/or too large fish), and controlling light (tank lighting and ambient room light). Use the watre changer to really move the grains of substrate aroound where the cyano is and it should float free, then it can be easily sucked out. Loosen all of it, allow it to settle down on the substrate, then it easily vacuums out.

Black brush/beard algae is caused by an imbalance of light/nutrients. Light may be too intense (bright), or not intense enough for the plants to use, or the wrong spectrum, or on for too long each 24-hour period. All of these "light" aspects must then be balanced with adequat nutrients for the plants to use the light, but not more. This algae on rock and wood is OK, provided it does not spread/is not spreading to plant leaves as that can in time suffocate the leaf and then the plant.
 
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